I don't even have those - but my rule is: regardless of who owns it, who runs it, who used to own it, who wants to own it, who buys it, who might buy it eventually ... if it doesn't have the word Harrah*s on it (and it doesn't fall in one of my other collecting interests), I usually don't pursue it.

And YES - that goes for RIO - SHOWBOAT & HARVEY'S... except slot cards. I collect those because people kept sending them so what could I do?