Sadly, the locks only help with the poorly equipped, or semi honest folks. I know I always have the tooling in my truck to easily cut locks off, even the expensive ones you're not supposed to be able to easily cut. Unfortunately, my only experience so far with an RV and thieves involved a TT stored in a storage lot for the winter. I had removed everything of value prior to storage, but they broke a window to get into the main trailer and popped the storage hatches with a crowbar damaging the doors and frames. While nothing was taken I still suffered a lot of damage.
Where I have experienced a lot of theft is a hiking or backpacking tailheads. When I lived in California, I had so much trouble with it I bought and old beater without a stereo or anything else worth taking. I would then leave it unlocked so they wouldn't do any damage getting into my car. It didn't help as twice they broke the door window to get inside anyway, without bothering to see if it was unlocked first.