I use the CG showers all the time. I don't stay at CG's with questionable bathrooms so it's never a problem.
I think you will find that those that use the showers more often are RV'ers that are full time, snowbirds, vacationers, etc. vs the weekend RV'er. The 'longer you are on the road' the more you yearn for a good ole fashioned shower!
I need the high water pressure, hot water and 45 minutes to ease my back pains after driving long hours. Just can't get that with the MH shower. Plus I don't have to waste the propane. Save that for when needed.
