Atlantis has always had schizophrenic thinking in its offers. I've played there for decades, only playing NSU Deuces, 9/6 Jacks, 10/7 DB, and the likes. I never got any offers until 2006-2007. I hit a sequential royal for $25,000 in 2008, and was amazed that I continued to get offers, even though I'd moved out of the area.
Then in 2011, the offers started dwindling. I'm thinking that some of the other posters got it right in their guess that anyone who wins has been "comped" enough. That seems to be the only thing that makes sense, particularly if the rumor of them no mailing a keno player who hit a big one. That's just plain stupid, and only an idiot for a manager would do that--such a player is the IDEAL casino customer, trusting on luck alone.
I'm thinking there may be more to the keno no mailer story, but I have no data or direct info to work with. Perhaps a +EV VP player or the like who tosses a few bucks into keno to mask or "enhance" their profile and just got very lucky?
At any rate, if they really are punishing winners, this will definitely come back and bite. Ploppies and stooges love respect, and will play losing games for the "privilege" of being respected and comped. Most even know they are losing, but like to think the comps and freebies make their losings a wash. It won't take long to chase them elsewhere if this is what their plan