When we have to camp in a campground instead of drycamping, we use either our RV's shower or the CG showers. Our main negative issues with CG showers are that the water temperature often can't be adjusted hot enough, or the shower head water spray is a terrible pattern, or the overall water pressure is poor, or last but by no means least - you have to drop quarters into the slot to keep showering ... it's really a tick-off when you didn't bring enough quarters along!
Ignoring the pay-for-the-shower irritation, I guess basically that it comes down to the "shower quality" at campgrounds being all over the map. At least our RV's shower is what it is so that we know what to expect each and every time we use it.
