Bellydancing is an ancient and cultured art. It's fascinating to watch, and takes a huge amount of talent. If a restaurant is hiring you to bellydance for them, chances are good that 1) it serves food from one of the same cultures that bellydancing belongs to, and the people who eat there will understand the meaning of your dancing, and 2) customers have already expressed an interest in seeing some form of cultural entertainment.
So, unless the restaurant you are bellydancing for is located directly inside a strip club, no worries! *grin* Have fun.