Most of the time it goes just fine.
A lot of people do "rent" their points but don't do "stranger rentals" - they rent to people they know personally (and can trust - because business arrangements between friends who don't pay are worse than the strangers). I have a list in my phonebook. Its all those people who when we say "we own a timeshare at Disney" say "oh, I'd like to go sometime if you don't use it" - and when they say that I do tell them what the deal would be. "I keep a list, I charge my friends my dues on the points - which would still be a LOT cheaper than a hotel room on property, I can put your name on the list - but I don't anticipate needing it" (and I haven't.)
(If I ever need the list, I'll start with the folks that 1) I can trust to pay me and not trash the room, leave unpaid bills 2) are most likely to have been serious enough when they said something and 3) have had talks about taking the kids to Disney that they haven't pulled the trigger on. I'm somewhat more likely to put the points up at our church fundraising auction though.)