Can't be bothered to look it up, but pretty sure I've seen a counting assistance that was done with pressure sensor pads, a buzzer and a uC in the sole of one of your shoes.
Casinos have a simple solution, they just throw out anyone who does suspiciously good for a long enough period of time (probably politely if they don't have evidence of counting).
"In other news, Las Vegas Casinos become the primary buyer of backscatter X-ray machines."