Googled it.

Q. My employer pays me less than the minimum wage because he includes my tips in my hourly pay. Is this legal?

A. No. Unlike under federal regulations, in California an employer cannot use an employee’s tips as a credit towards its obligation to pay the minimum wage. California law requires that employees receive the minimum wage plus any tips left for them by patrons of the employer’s business. Labor Code Section 351
That's the only way to do things that makes sense to me. The fact that other states do it differently kinda boggles the mind. Tip is entirely voluntary, how can employers act as though that's part of a employees regular pay?