The major problem is the ethics of tipping. In the U.S. tipping puts (all if not most) jobs into a category which employers now pay a sub-minimum wage. Legally the employer isn’t responsible for a federal minimum wage anymore because it is assumed tips will cover the rest of it. In actuality with taxes, many people don’t get a paycheck because of how little they earn. It just went to taxes.
EDIT: Imagine working full time (40 hours) and getting a piece of paper that says “THIS IS NOT A CHECK” telling you how little you earned.
Unless you’re talking about somewhere other than the US or you have some crazy locality, this doesn’t sound right.
In the US, the employer is legally obligated to make up the difference between what the employee earned (wage plus claimed tips) and minimum wage. In fairness to your point, that’s not a big help since the federal minimum wage is a joke. If they’re failing to do that, they’re breaking the law.
Additionally, taxes should be a percentage of their earnings. How would they be ending up with zero dollar paychecks after 40 hours?