most National Parks don't have any hookups. Yellowstone is one of the few and it only has one CG with hookups., Fishing Bridge.
Yosemite does have some large sites in North Pines that will accommodate larger rigs. not sure about the other two.
since you're from California, you should be used to park campgrounds not having any hookups, since California State Parks have only a handful statewide. and they're booked up nearly year-round.