Servers still have to receive the standard minimum wage. If their tips don’t bring them up to that level, their employer has to make up the difference. Of course, not all employers follow the law, but that’s the requirement.
The other states just have to find a reason to can them so i imagine its "somewhat" more difficult.
A lot of States (or maybe cities) have much much higher minimum wages for servers than my state. California, Las Vegas, and maybe New York pay higher than the $2.