It's very tourism drived, there are some bad areas yes, but the development has pushed those areas away from the tourists with barriers, etc. to avoid problems. Yes, some people do still experience theft in some locations. Keep things locked and keep windows closed and items of value far from view. The DL parking garage was robbed not too long ago, but they were after the money from the attendant.
Stayed at some not so great places over the years - even before the nicer development started happening. I don't think you're any less safe there than at some other hotel. If you're very concerned, call the management at the RV park and ask them if they have had any incidents at their location.