I've been counter-measured and backed off from further play (for refusing to show ID) from Ameristar (St Louis & KC) more times than I care to count. I imagine if they were "card clumping" or cheating in any form, they probably would have just allowed me to play unmolested.

Out of sheer coincidence though, I believe I'm a life-time loser at Ameristar St. Louis. Majority of my life-time losses though are the result of a couple sessions that went horribly "wrong." AKA: Extreme Negative Variance. But that obviously wouldn't deter me playing there anymore. I just don't anymore (or regularly anyway) because it only takes the pit (or EITS) a few min to identify me, so it just isn't worth the hassle most of the time.