As you state, quite correctly, it is "casino policy"
However, certain other people STILL insist it is NV State Law.

There is a HUGE difference. Some conventions HAVE been smoking. Its been witnessed.
How did that happen? Maybe some convention organisers politely suggested to Mr Gaughan that they might look for 'smoking premises' elsewhere. He can relax the rules whenever he wishes. After all, its ONLY casino policy, NOT state law.