It's completely logical. If you value a silent car ride, or more significantly, if you value not being asked for money by someone who has you trapped in the back seat of their car and whom you are trusting to get you to your destination, then you would pay more up front for a ride free of hustle for a tip.

Is the back seat the de facto protocol? I always sat in the front. It somehow feels more friendly and personal. But in a taxi, I'll usually sit in the back.

Lyft started out with sitting in the front as the standard protocol (which is no longer the case), but AFAIK UberX has always been back-seat & taxi-like.

I moved coasts and city sizes, riding uberX a lot in both. East coast big city was strictly back seat. Continued the practice west coast smaller town and had a couple drivers mention it was unusual when I asked.

The front has the airbag. Nothing personal, but I'll be up there.

Use Lyft? They have tipping and are generally nicer.

They are also not as widespread.