Only after they get out of the hospital, by which time I would think that you'd find someplace else to stay. But you are correct, never take a knife to a gun fight.
The reason I mention the bear spray is because it has some advantages beyond the over the counter pepper spray. One of which is the potency factor, also it comes in a a grizzly bear size can, you aren't going to run out in just a few seconds. Also it is extremely easy to aim, designed to hit the target with the product at a distance of 20 feet with a wider spread than personal defense pepper spray.
Guns are not for everybody, even someone with extensive training can hesitate to use deadly force even though the situation might warrant it. Non-lethal deterents can be a viable option for those who are not only uncomfortable with firearms but those who have not trained in their use against people. I have been in a situation one time where deadly force was warranted and I hesitated, it could have cost me my life, that taught me a VERY important lesson and if the situation should ever happen again the outcome WILL be different, I'm much older and wiser now.
Crimes committed against folks in RV's are rare, we tend to be of an age that lends itself to self-awareness and the average RV'r doesn't tend to intentionally put him/herself in harms way unnecessarily. Also if you ask around you might find that a lot of RV'rs do tend to have firearms in their rigs which in and of itself "I" think is a deterent.
Robert A. Heinlein stated (1939?) that: An armed society is a polite society. Manners are good when one may have to back up his acts with his life."