I think it's all about money. The power windows, mirrors and locks help the manufacturer justify a higher price on the MSRP. They save money by not having to design and stock the manual components, not having to train someone to install the manual components, etc. They make money by selling repair parts and services when they fail sometime down the road.
I could not care less for power windows and mirrors, but power locks are important to me so I can have remote keyless entry. Much nicer as I run toward the car on a rainy day.
And, I kinda like power seats, because my wife is short. With power seats, she moves forward and upwards and she appreciates that. Not too many manual seats in the domestics go upwards. At least they did not in the past. I've only been driving an import for a bit over 2 years now. {Not likely to by another Kia to replace this one though.}