Yeah, when I first moved to the Kansas City area from St Louis that was one thing that took some getting used to.
That, and highway exits on the left.
The 10, of course. Look where I am.
You’re a rarity, methinks. Although most native Angelenos like myself know the names of all of the freeways in Greater LA, I don’t ever hear anyone use those names other than traffic reporters.
Most of my friends are now a straight shot off the 101 from downtown, but when I lived farther out, it used to be the 10 to the 57 to the 210 to the 134 to the 101. Easy as pie. 
Western New York is weird about this. First of all, any interstate is called “the Thruway”, whether or not it is the Thruway (the I-90). Second, “190” and “the 190” are interchangeable…I’ve heard both. Third, I-290 is almost universally known as “the Youngmann” or “the Youngmann Expressway.” Then there’s also “the Scajaquada” (NY-198) and “the Kensington” (NY-33).
I know it’s been covered, but I have to reiterate: no we don’t.
Also, it’s not 70 and sunny on perpetual beaches “in California.” Ask any of the shivering tourists in shorts at Pier 39.
Being from Michigan, I have a hybrid approach. In Michigan, it’s (e.g.) “I-75,” sometimes “interstate 75,” or sometimes just “75.” When talking to some old people (and when having to listen on the radio), it’s “the Chrysler.” (Similarly I-94 is “the Ford,” and 696 is “the Reuther”). Ah, but here’s where we go hybrid: On the other side of the river, it’s like, “take the 402 to the 401 to the 403, and then get onto the QEW,” or “head west on the EC Rowe.”
Down here in Mexico it’s cumbersome. All of the major highways have route numbers, but in all popular speech and written communications, they use the name of the anchoring cities. In many, many cases, the official street signs don’t mention the route number; you have to know the next trunk city’s name rather than relying on the route number! So I literally could 57 and/or 57D all the way to Eagle Pass from Santa Fe (Mexico City), but every stretch has it’s name. You take the Mexico-Queretero, or you take the Campanche-Lecheria, or you take the Libremiento San Luis Potosi.
Northern CA, just use the numbers. 99, 32, 149. I-5 can be called that or just 5. Also, 5 is the only one that really qualifies to get the I in front very often. Sometimes 80. But you would never say I-880 or I-280.
Even on the Central Coast where I grew up nobody called it the 101.
Mine is the M40.
I don’t think I’ve heard anyone in the UK refer to any motorway as anything other than “the M##”.
ETA: Though Chris Rea did write a song while in a traffic jam on the M25, where he called it “the road to hell”.
In Las Vegas. I have never heard anyone refer to a freeway as just the number. Freeways here are either “(name)” or “the (number)”. For example, the 95 goes southeast to northwest. Summerlin parkway goes from the 95 to the 215.
The freeways in Los Angeles get a “the” because they aren’t mere roads but places with their own particular rhythm and flavor. There’s a reoccurring segment on Robot Chicken about a super-villain carpool caught in a traffic jam. Part of what makes it funny (if you know L.A.) is that they’re always stuck on the 405 at the Sunset exit. How many freeways have enough personality to carry a joke?
“Ha, ha … yeah … that’s the 405 all right … they really nailed it!”
Another central Californian, everybody here refers to the number without the leading “the” - so it’s 80, 580, 980, 280, etc.
Not “the 80”.
In Central Texas it’s I-35, 35, or even IH-35.
Never “the” 35.
When I lived in San Luis Obispo, we referenced the 1 and the 101.
In Boston, it’s 95, 93, 128 (sometimes “route”) and the Masspike (I-90). A lot of travel is done on US highways which are always “Routes” - Route 20, etc. But I also saw people (and signs) refer to the interstate as “Route 95” or “Route 495.”
That’s just a Southern California thing; we do say “the 405”, “the 10”, etc. In Northern California they omit the “the”.
I don’t know about elsewhere but forty or fifty years ago it was more common to use the name of the freeway, e.g. The San Diego Freeway (which doesn’t actually go there!).
In San Diego I noticed people saying “I-5”, “I-805” without the article. However, I was in college at the time and we had a lot of guys from the Bay Area in the dorm.
Most freeways in the metro Detroit area have names attached to them as mentioned above, and always use “the” with the name, but not with the number. “The Lodge” or “M-10.” You also here both the names and numbers on traffic reports these days. MDOT has heavily pushed the use of the numbers; there’s a sign near downtown for the junction at M-10 (with I-75 I think), the Lodge, which has only the number in the diamond (indicating a state road) and the distance. No control cities (no one cares, it doesn’t go that far), no Freeway name (John C Lodge).
The names are actually sometimes more useful than the numbers due to them being built before the interstate designations. You have the Fisher and the Chrysler both as I-75 - the former south of downtown, the latter north. You have the Jeffries as being I-96 specifically between downtown and the I-275 interchange, and you have the Lodge specifically where M-10 is a freeway - it gets called something else when it turns into a surface street.
“The” is only used for the freeway section of roads. Southfield Road turns into a freeway (M-39) for a significant portion of its existence. The road is always “Southfield [Road]” while the freeway is always “the Southfield [Freeway]”. Even in areas where there is semi-restricted access to roads such as Ford, Telegraph, and 8 Mile (each of which has state highway numbers no one uses), they are thought of as roads even if there are labeled exits and no lights for miles.
The ‘I’ part of interstate freeways tends to get dropped: you have 696 and 275, but US highways and state roads invariably are called US-24 or M-10.
Personally, I use “the Lodge”, “the Davison”, and “the Southfield”, but rarely any other freeway names. I have no problem understanding where the Fisher, Chrysler, Jeffries, and Reuther are, but again, I don’t use them. That the former are all state highways and the latter are all Interstates may have something to do with it.
You are clearly living in the wrong half of California.
That much is obvious from his name.
I disagree. We normally called it the 101. The only exceptions I can think of are Highway 1, which only gets a the if it’s called the PCH, and I-5 but that loses the I once you get into LA and becomes the 5.
In Australia (well, certainly in Victoria anyway) freeways are rarely known by their numbers but always have names assigned. So we have The Hume, The Princes, The Monash, The Eastern, etc etc.
I’m not a rarity, I’m just older than you. Also, not very good with numbers.
We used 101 for a specific stretch. I don’t remember where. (Also bad with geography.)