Take your average mid-sized sedan layout (though this is the view of an SUV, it should illustrate the idea for anyone who has never been in a car before.):
You have a driver's seat and a passenger's seat up front, and a bench seat in back for a few more.
Since all the driver controls are concentrated around a single seat, and that single-seat needs to be facing the road to be functional, this configuration makes a lot of sense.
With driverless cars being developed, what sorts of shifts in the layout of the seating will be made if the need for a dedicated driver's seat is eliminated?
I was trying to think of comparisons to current vehicles, but none exist. Taxis still have a driver. Limousines are significantly different in size and are not a daily vehicle (for most of us). Trains are designed for mass transit peak usage instead of personal use.
Here are two charts showing how people currently use their vehicles. Most trips will be 15-25 minutes on the way to go shopping or to go to work.: