Some restaurants stipulate a 10% waiters-tip.

Answer

The 10% waiter-tip imposition is haraam. You do have a choice. Simply don't eat at such a haraam restaurant. Their food is unwholesome and haraam. Eat the halaal tayyib food prepared at home. If you do not consume halaalized carrion and the deluge of haraam processed junk, then your food at home will be halaal and tayyib. Don't visit the restaurants.