In the case of the Minnesota Twins, there was a logical explanation. Before Calvin Griffith moved the Washington Senators to the Gopher State, the Twin Cities had two teams in the AAA (highest level of minor league) American Association, the Minneapolis Millers and St. Paul Saints. In order to avoid picking one city name and thus potentially alienating the folks on the other side of the river, the club (actually based from 1961 to '81 in Bloomington) went with the neutral “Minnesota” option. See the original logo’s depiction of “M” and “STP” coming together in friendship.
On preview, I see Wheelz has covered this situation and included “bonus” material, but as my paragraph contains some additional information, I’ll leave it as is.
The Texas Rangers’ story has some similarities to the Twins’. When the “new” Washington Senators (who joined the American League as an expansion team the same year the Twins debuted in Minnesota) moved to the Lone Star State, they opted to call the city of Arlington (part of the Dallas-Fort Worth “metroplex”) home. Rather than playing favorites by picking one city, or awkwardly stringing together the names of two or three municipalities, the club’s brass decided to embrace the whole state and, not incidentally, play off the legendary reputation of the law enforcement unit known as the Texas Rangers.
Also contributing to the use of state names was the NBA’s one-time rival, the American Basketball Association. The ABA’s Carolina Cougars, for example, played home games in Charlotte, Greensboro, Raleigh, and Winston-Salem in order to appeal to as many North Carolinians as possible. Similarly, the Virginia Squires variously hosted games in Norfolk, Hampton, Richmond, and Roanoke.
Although neither of these teams joined the NBA as part of the partial merger with the ABA, the Indiana Pacers made the transition. Although based solely in Indianapolis throughout its history, the team opted to be as inclusive of the Hoosier State population as possible. Not only was the geographic part of the name thus easier to say and write, the team had an “out” had crowds in Indianapolis not been satisfactory. The franchise could move to Fort Wayne (in which the Pistons had been based before moving to Detroit) or Evansville, but the logo wouldn’t need to change!