I had a compact sedan for a long time, and can confirm your observation. In fact, it worked best for me to feed the bass into the driver's side rear door (of a 4-door car), scroll first, and then upside down in the passenger seat.
Now I have a little hatchback, and am quite happy. Granted, transportation is still an issue -- I'm floored when I hear about bassists getting around in NYC using cabs, the subway, etc. But it's the only instrument that I play well enough for anybody to actually want me to play it, and I do love the bass.
A guy I know squeezes his homemade mando-bass (still a large instrument) into a Karman Ghia. Only he knows the magic twists and turns to get it in and out.
I had an old 86 Honda CRX (two seater), and figured out how to fit my bass, amp, and two cellos. I'm pretty sure I couldn't do it again. The main trick, though, is to recline the passengers seat and sit the bass in it.
I dunno if it helps, but when I started I did not know I could put it in the front seat of most cars with the seat laid back. That's made transport relatively easy ( though it is a very bulky instrument).