Originally Posted by
ohmark
True, but irrelevant. Generally, a business is free to enforce MORE restrictive rules (e.g. Marriott), but not less.
According to the OP, they had a license for their event. I seriously doubt the Marriott Marquis was openly violating the NYC (or NY State) smoking laws. I don't understand how the licensing for a smoking event works there, but whatever it is I'm sure Marriott followed it.