Not true. It depends on the job and the state. NY for example, has a tip allowance of $5 per hour. That means establishments can pay their servers $10 per hour and still meet minimum wage law, because the staff is expected to make at least $5 per hour in tips.
While I agree that employers should pay their staff well, it’s standard practice for servers in NY to be underpaid and rely on tips as part of their income.