I took my 14 year old RV into a 55 and older park in Mesa AZ the first week of June 2008. I stayed until December, with my car, a work truck and I was only 43 at the time.
The owner is VERY picky about who he lets stay in his apartments, and I offered to repair one of the air conditioners as I pulled in. We still talk to each other, and he asks questions about air conditioners from time to time, and has avoided calling a mechanic a few times now. . . He is picky about his apartments because even being a 'little' picky, he still has to spend more than 30 hours cleaning and restoring the apartments back to livable place each time. However in summer, he is very happy to fill any of his open RV sites, and does not bring in enough income to cover expenses each summer.
Yes it is a tool to keep out poor looking RV's. However it does not always work. One owner of a 1984 Bluebird was sent home one weekend, and bought the RV park the next week, returning with his 'own' rules!
Fred.