And most of them are usually not near a toilet. While the parts are cheap, it's not a trivial matter to install an outlet where one hasn't been planned in a finished room.
I don't think I agree with that. Every home I've lived in has had a GFCI outlet within four feet. (Usually on the side of the sink, next to the mirror. Also usually adjacent to the toilet.)
(My current apartment has four: two in the bathroom, two in the kitchen.)