There have been posts that did analyses on 100K plus hands and found every to be random. Someone else can post the links.

Besides, that, it's incredibly stupid and very bad business. The bottom is that such strategies would be found out sooner or later by looking at 100K or so hands (if they did it enough to affect the bottom line it would be noticable), and the scandal would cause them to their incredibly profitable business. It's entirely in their interest to be completely above board.

It's just common sense.

Since you posed the question, see if you to come up with a way they could rig the deck without detection.