My customer facing time was in a different industry, HOWEVER, that is not what I heard.

The jist was that the /minimum/ wage was what the worker was required to take home, tips inclusive, and that if they couldn't clear that bar (the restaurant had to pay them more) they were retrained and/or otherwise moved around until they either could or quit on their own.

Sure, they may be fired or moved around. However it's the law that they must make at least minimum wage for the hours worked.

https://webapps.dol.gov/elaws/faq/esa/flsa/002.htm