The impression I get is you are from another country, rather than the USA.
Within the USA, there is not a casino or gambling facility that will allow a dealer or a host to play within their facility when off-duty, never mind on duty, that I am aware of.
As far as a host playing, I have witnessed a few hosts sitting with their players for a short period of time to shoot the breeze, as the saying goes. Never ever engage in gambling.
Must be something they do within wherever you reside??