I've been reading about Vegas comps, about how casinos "reimburse" your expected gambling losses with free stuff, which sometimes include free hotel nights. I've also read that if you are on their gambling loyalty program, they send you things like free nights to entice to you visit them.

Couple of questions:
1) Are these nights really free? Do you have to pay a resort fee for these free nights?
2) Can you get "free nights" by just signing up for the gambling loyalty program, but not gamble a single cent?
3) If I practice advantage gambling on Blackjack, is it possible to get "free nights" and not lose any money? I read that with practiced card counting in Blackjack, the odds are in favor of the person gambling by 1-2%, so technically it's possible not to lose. So will they still give comps if you are playing and winning?