They depend on tips to pay their bills.

他们靠小费付账。

youdao

Of course, in addition to my weekly pay, I got a lot of tips.

当然，除了周薪外，我还得到很多小费。

《柯林斯英汉双解大词典》

Studies in restaurants show that the tips left by customers who pay their bill in cash tend to be larger when the bill is presented on a tray that bears a credit-card logo.

对餐馆的研究表明，当账单被放在印有信用卡标志的托盘上时，用现金付账的顾客往往会留下更多的小费。

youdao

The Dodd-Frank financial regulatory reforms passed in the summer of 2010 empower the SEC to pay bounties for tips submitted by corporate whistleblowers.

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By having an IP recognize how they can become an IP for their company and giving them tips on how to approach the company with alternatives (pay, hours, etc) you have helped enlighten the managers as well.

FORBES: Connect

But in 2006 Congress ordered the IRS to set up a Whistleblower Office, look at all tips and pay a minimum 15% bounty on collections.

FORBES: Magazine Article