..you win $11,000 playing BJ.
You give your chips to a friend to cash in for you.
NV regs say "there must be proof of gaming" for that many chips to be cashed in.

The cage calls the pit for "proof" (pit manager can not ID your friend) as gaming in the casino, the chips do not have to be cashed and may be confiscated.

NV regs say chips are for gaming. No proof of gaming, no cash the chips.

Short version of a very complicated NV reg made to comply with IRS law..