One very signigicant difference between airline and casino programs:
With airline programs, they are very public about what you need to do to earn status, what your account balance is, what is needed to earn a reward, etc.
With most casino programs, all of this is very much cloaked.
Exactly how long do I need to sit at the blackjack table betting green before they'll buy me dinner? Before my room will be comped? Before I earn Harrah's status? I don't get monthly statements from them...