Jason, I don't get nearly 50mpg in my Golf, but then I drive mostly in heavy stop and go traffic. In bad conditons I get maybe 33-35 mpg. I've seen 45-48 on the highway but I rarely ever get to drive for long periods of time without a traffic jam. Mostly if I go out of town it's to spend a weekend with friends in Morro Bay. That's 200 mostly highway miles each way, but on the return trip Sunday afternoon the 101 always, always backs up and stops dead in Santa Barbara. So I spend an hour in first gear doing what should be a 20 minute drive, and any mileage measurement goes to hell.
Also, my car is slightly modded to run more boost. It really helps on those metered uphill freeway ramps, but of course there is a mileage hit. Still, it gets better mileage than most anything else I could drive, short of a hybrid, and it's mine so I'm keeping it in spite of its many foibles and the complete lack of VW dealers who know anything about a diesel car.
If I get another vehicle in the near future it will be a motorcyle. I've never been interested in them, but the ability to use the car pool lane and to lane split would be a huge help in keeping appointments.