I think a BIG reason for FWD is its inherent superiority in terms of predictability, and superior foul-weather traction. In probably 99% of the applications, FWD is in a car with the motor in the front. That same car probably also has more weight up front, hence more weight on the drive wheels=better traction. Also, what happens when you break traction in a FWD car? The answer is...not much, a little push/understeer, that's it. In RWD, if you get enough slippage then you might just swap ends. Bad for business...which is another reason why most cars, FWD or RWD, have a dialed-in tendency to understeer. It's considerably more idiot-proof.
For the record, 2 RWD's in this household; I'd rather have to buy snow tires than foresake all the benefits of RWD (Fun-to-drive)!