They do sell street legal golf carts that can be driven on roads up to 35mph! They are titled and registered as a car. So they can be driven around as one. Yes there are some campground/resorts that are big enough that one is required. Otherwise i've been in campgrounds where you could walk te entire place in 5 minutes and quite a few people had them. It's all about your lifestyle.
I was at a campground last weekend and i went into town for some stuff. The town i went through was "golf cart friendly". I guess they figure there will be less pollution and less serious accidents on golf carts.