Comment by Doxin

In Minecraft one of the common ways to catch people using x-ray hacks or transparent texture packs is to run statistics on the blocks mined. If the ratio of stone-to-diamond gets significantly out of whack it's a sure sign someone is cheating.

In blackjack card counting is (probabilistically) caught by tracking player winnings. If someone is beating the odds a bit too much it's a fairly good indicator they are counting cards. Of course in this case getting it wrong isn't so bad from the casinos perspective either since then they'll just kick out a player that was costing them money anyhow.

When the enigma cypher got cracked they had to be very careful about when to act on information gained. If they started beating the odds too much the Germans would cotton on to enigma being broken.

My point being that cheating will almost by definition improve your odds. There are definitely ways to catch that sort of thing happening without installing rootkits. You just might need to hire a couple mathematicians to figure it out.