A minimum wage is just that, a minimum. A minimum wage provides necessary security, and decreasing it simply isn't fair. Not all servers make the tips that steak house servers do, and not all hours are busy, nor do all customers tip. A decrease would mean potential hours when servers could make less than the law requires us to be paid. There is simply no way to anticipate or regulate tips on a given day.
Tips are gratuity.
They are a reward for good service, and tips are extra. They are not mandatory and cannot be considered as an absolute factor in one's income. Restaurant owners should have to adjust to the minimum wage increase just like every other business. There is no logic in increasing the minimum wage for some and offsetting it by decreasing the minimum wage for others. Doing so suggests some workers' aren't as valuable as others.