This is something I’ve always been curious about. I’m not a sports fan myself, but if I were, I feel like I’d be a fan of whatever city I’m living in (Or a fan of whoever the locals favor).
So I guess the question is: If you currently root for your home team, and you moved to say Chicago, would you start rooting for the Bears or Bulls?
I grew up in Chicago. I was never really interested in sports growing up, but as a teenager I moved to an exurb of Chicago, near relatives who were big Chicago sports fans, and I became a fan of the Bears (NFL), Cubs (MLB, National League), and Bulls (NBA). I kinda vaguely followed the Blackhawks (NHL) and White Sox (MLB, American League) as well.
After moving to North Carolina, I remained, and remain, a Chicago fan. I added the Panthers (NFL) as a secondary rooting interest, but don’t follow them particularly closely. I don’t follow the Hurricanes (NHL) or Hornets (NBA) at all.
tl;dr I didn’t change teams after changing cities, but I did add a new team as a secondary rooting interest.
I grew up in the Bronx, but as a kid I was never a serious baseball fan. My family traditionally were NY Giants fans, so when they moved there was no family tradition to follow. I started to root for the Yankees after I had moved to Boulder, Colorado, during their run of World Series in the 1970s. When I moved back to the Bronx for a couple years in the 1980s I went to a lot of games, and I’ve remained a fan after moving to Washington DC and then Panama.
When I moved to DC I used to go to Orioles games in Baltimore. I would root for them as long as they weren’t playing the Yankees.
In the NL, I’ll generally root for the Mets, again as long as they’re not playing the Yankees. I’ll also root for the Nationals, even though I moved long before they came to DC.
In the NFL I root for the Giants. When I lived in DC I could never bring myself to root for the Redskins, even though they were very good at the time, and never became a Broncos fan in Colorado.
My interest in hockey and basketball is marginal, partly because the New York teams have rarely been good in recent decades.
I grew up in Boston, but have spent the pas 35 years living outside Manhattan in New Jersey.
I’m a huge New England sports fan, and current having the time of my life. The Red Sox kicked some Yankee (and now Astro) butt. One of my dreams is to see The Pats beat the Giants in the Super Bowl.
Not exactly the same thing.
My father grew up a Brooklyn Dodger fan. My mother is a huge baseball fan overall but specifically a yankee fan. In the 80s I would say I was a Mets fan. I loved their run in 86. Then I went away to the Army. I pretty much didn’t watch a baseball game for 4 years. When I got back home my mother was watching the Yankees. You could feel something building. They had exciting young players. They were really fun to watch. And my local cable company made it almost impossible to watch the Mets. You had to pay extra and the signal was awful. And the team was awful. So the combination of watching every game of a young exciting Yankee team. And not seeing most games of a badly run Mets team turned me into a yankee fan.
I can’t recall ever changing teams, but I did partially add some rooting interest.
I have always been a fan of the Cowboys and Stars. But when I lived in upstate New York, I began rooting for the Bills and Sabres too. (A bit awkward considering the 1999 Stanley Cup)
Didn’t lose any loyalty to the Dallas teams, but gained some 0.5 loyalty to Buffalo.
Casual fans do that, the ones who claim to be “a huge fan” whenever the local team goes to the playoffs even if they can’t name more than two of its players. But sports fandom is the essence of tribalism, and you can’t easily change a deeply held tribal affiliation.
In Florida, a very large number of residents come from elsewhere, bringing their fan affiliations with them, and the mass of fellow fans is far enough beyond critical that it’s easy to keep them. You’ll see that at, say, Tampa Bay Rays games against the Yankees or Red Sox, where the majority of the apparel on fans in the stands is of the visiting team, worn by their transplanted fans. Sports bars specialize in hosting fans of particular teams on game days, too - for instance, there’s one in town that has Steelers stuff on one side and Packers stuff on the other (we don’t go there 
). The Patriots and Eagles bar somehow has a group of Chargers fans in the middle (yes, Chargers fans in Florida - go figure). But I can imagine how the pull of the local tribe could overpower the pull of the former tribe in other areas, when not surrounded by fellow transplants.
Bill Simmons had a good essay on Sports Bigamy.
This is me.
I’m never not going to root for the Packers and Brewers no matter where I live, but since moving to Florida I’ve adopted the Lightning as a team I follow.
I have a bit of a soft spot for the Carolina Panthers because I saw what a great relationship the team has to the city of Charlotte. I don’t ACTIVELY root for them, but I don’t root against them either.
Not exactly the same thing, but…
I’ve never moved out of the area, but I grew up with the Orioles and the [del]Expos[/del] Nationals came to me. Even thought the Nationals are much, much closer, not to mention a much better team (relatively), I still stick with the O’s.
This, for me, too.
I grew up in Green Bay, went to college at the University of Wisconsin, and moved to the Chicago area after I graduated, where I’ve lived since.
I was a big fan of the Packers and Brewers when I lived in Wisconsin, and that never changed (even though the Brewers have wandered in the wilderness for much of the time that I’ve lived down here).
I wound up marrying a woman from Chicago, and I adopted the White Sox as a secondary team, since my wife and her family are all Sox fans. I also became a Blackhawks fan, though, as Wisconsin doesn’t have an NHL team, that was a matter of adding a team rather than changing.
My sporting team rooting hasn’t changed significantly since my childhood days growing up in the desert north of Los Angeles. I root for the Cubs because my dad was from Chicagoland and I got taken to Cubs games at Wrigley Field when we would visit. I root for the Packers because my uncle (dad’s bro-in-law) turned me into a Packer fan as a kid during the Bart Starr years by sending me Packer stuff (it was a big practical joke on my dad, who, as a Bears fan, seethed watching his eldest child turn into a lover of green and gold). I root for the Bengals because in about 1969 or so, as a kid of 9, I decided I needed to root for an AFL team (the intricacies of the merger were a bit beyond me), and I loved the idea of a team named after Bengal Tigers (I also liked their quarterback, Greg Cook). I root for the Maple Leafs because I loved their sweaters, and I think my first season of “rooting” for them was their last season as winners of the Cup. I have no rooting interest in the NBA (don’t really watch it, and never have much, though I certainly recall the voice of Chick Hearn for Lakers games).
I never rooted for the natural “local” LA teams for some reason. Generally, I either despised or pitied them. The Dodgers and the Lakers, I despised. The Angels and the Kings I pitied. The Rams just kind of existed; how can you despise a team with the best helmet in the NFL? Because I never was a fan of the “home” teams, my peripatetic life journey hasn’t required me to adjust this rooting scheme.
I never developed a rooting interest in any specific college football or basketball teams, either. Southern Californios don’t generally get all excited about the “local” universities (UCLA, USC, San Diego St., etc.). I would have a team I generally preferred in all the rivalry games (Mich over OSU, but paradoxically, Mich. St. over Mich; 'Bama over Auburn; Oklahoma over Texas; Arkansas over Texas; Cal over Stanford; USC over UCLA; etc.). Those preferences haven’t really carried through in all cases; my time living in Ohio turned me into a Buckeye rooter in the Big Game. I went to a Div III school (U of Rochester), which never had a particularly good team (five wins is a good season!). And while I love watching college basketball, I just generally root for the underdog to make a good game of it.
In the late '90s, as the English Premier League games were getting more regularly broadcast, I decided to add a team from England to root for. Kasey Keller was the USA’s best goalkeeper, and he had just moved from Millwall to Leicester City, which had just been promoted to the PL. So I chose that team to root for, and I have stuck with them through thin and thick.
I live near to Charlotte, NC now. I am happy when the Panthers do well, because it makes the locals happy, but I don’t really root for them. I pay no attention to the Hornets. There are no other “local” major league teams. So I am quite cozy rooting as I always have!
Not a sports fan here, but I was thinking about this same thing recently - glad you posted. If someone is peripatetic, I can understand sticking with a previous team. But if a relocation is longterm/permanent, I find it harder to understand - why you would WANT to be out of line with your new friends/community.
Another wrinkle (sorry if this is a hijack) is why someone living in a major sports outlet chooses to be a fan of a DIFFERENT team (assuming the home team doesn’t completely suck.) Growing up in Chicago, I started off a Cubs fan, until my 9-year old self figured 69 was unforgiveable. Then switched to the Sox, abetted by my older sisters’ BFs who were big fans.
B-ball, I liked the Bucks, because I was a HUGE Big-O.Lew Alcindor fan. And the Bulls pretty much sucked.
Bears COMPLETELY sucked, so I was a Vikings fan - til I got tired of them ALWAYS finding a way to lose the big game!
I suppose it’d have been different if I’d relocated from Wisconsin to, say, Kansas City – the Chiefs aren’t really a rival to the Packers. Being a Packer fan in Bears territory, if nothing else, leads to an opportunity for good-natured ribbing (especially because the Packers have generally been a lot better than the Bears for most of the time I’ve lived here). And, it also gives us few Packer fans here a reason to bond. 
But, an anecdote related to your thought of “not wanting to be out of line with new friends.” My wife’s late grandfather grew up on the north side of Chicago, and was a hardcore Cubs fan when he was young. In his 30s, he started a job as a machinist at a Chicago company where many of his fellow employees were, in fact, White Sox fans. He wound up changing his allegiance to the Sox, so he could fit in with his co-workers, and have something to talk about with them.
I never did. I always found the fans in any new city to be insufferable. 
I’ve never been a huge fan of pro sports, just a casual one. Maybe that’s because I’ve never lived in a pro sports city. My Dad was and still is a huge Cubs fan (he’s from Chicago), but I never took an interest in baseball. I did like the Chicago Bulls when Jordan was there, but after he retired I became an Orlando Magic fan (they were the closest team to me). I haven’t followed the NBA at all really since I left Florida. I’ve never cared for the NFL. And what’s hockey?
I grew up a huge college football fan (Florida State), and ended up going to college there. I’ve maintained my loyalty even after moving to Alabama. It is my alma mater though, so it’s more than just fan loyalty.
I grew up about 45 minutes north of Philly but then went to Pitt for college. It was around the time when the Eagles were flying high under McNabb and going to four straight NFC championship games and the Steelers just drafted a guy named Roethlisberger. My friends were cool at Pitt and we always rooted for an All-PA Super Bowl. And even though it never happened (came close a few times), I ended up cheering for the Steelers when they won it all in Super Bowl XL in 2006. It was super fun “rioting” on the Pitt campus after their big win!
Nope. I’ve lived in many states over the last 30 years or so, but I’ve always been a fan of the New Orleans Saints, Alabama Crimson Tide, and Mississippi State Bulldogs. Likely always will be. I’ve liked other teams at different times, but those three are constants.
My father was an interesting kind of sports fan who was more interested in strategy and execution than he was in a particular team or player. In the pre-Internet days the only way he could dive deeply into statistics, the coach’s thinking, the current injury list, etc. was by following the team that got the most media coverage - i.e., the home team. He had no problem shifting his fandom from the Bears to the Cowboys, to the Cardinals, and back to the Bears as he moved around.
These days he’d probably just build a fantasy team of his own.
It depends.
I grew up in Illinois, rooting for the Cubs & Bears. I’ve since lived for several years in California and the last 7 years in Texas. I never wavered from my loyalty to the Cubs & Bears. But I also never developed any kind of interest in hockey until I had an Air Force roommate that turned me onto that game. So for a long time, I was a Kings fan but I never really had that deep bond I had with the teams of my youth. When I moved to Texas, I started going to several AHL games every year with the Stars’ affiliate, so I primarily root for the Stars now because I’ve watched a bunch of those guys come up through the minor leagues. But still, while I’d love to see the Stars win a Stanley Cup, it would never have the emotional impact that seeing the Cubs win in 2016 had for me.
To kinda-sorta answer this question, other than the Packers I’m also a lifelong Dolphins fan for the simple reason of me really liking dolphins (the animal) as a kid and getting a bunch of Dolphins stuff to wear because “hey, cool a dolphin!”
Once I matured as a sports fan I just kinda never left 'em.