Both in federal law and most state laws, tipped workers have a lower base minimum wage, but have to be “topped up” by the employer to the general minimum wage if their tips are insufficient (but as tips are also frequently used as a performance measure, and many tipped professions are high-labor-supply fields where vacancies are easily filled and thus employers are quick to let people go, tipped employees that would need topped up are under pressure to pad their own tips to protect their job.)
If tipped workers had the general minimum wage as their base minimum wage with no top-up requirement, much of the abuses would go away (and there'd be less employer desire to drive the practice, but the culture would probably endure for some time.)