It shouldn’t be, but it’s US law.

https://www.dol.gov/general/topic/wages/wagestips

An employer of a tipped employee is only required to pay $2.13 per hour in direct wages if that amount combined with the tips received at least equals the federal minimum wage.

Fuck this law, and fuck employers that try to skirt around it when tips are too low. Also fuck employers in general who aren’t willing to pay their employees a living wage.

I tip for waiting jobs because I know people work for shitty employers and it’s their primary income source. But I hate the system, not the people who need tips to get by.