Working in food service can be a thankless job. While waiting on tables, you’re supposed to be nice, friendly, and helpful, but the customers you’re waiting on might be the exact opposite. It can make for a long day (or night) of work.

The least customers could do would be to leave an appropriate tip when they leave. It would be even nicer if they leave a generous tip if their server went above and beyond to help them in some way, like describing items on the menu or offering advice.

Not all customers are thoughtful or generous. Some customers don’t even leave a tip at all. In some cases, customers wrote a note on the receipt explaining why they weren’t leaving a tip. The note hardly replaced the tip the waiters and waitresses depend on to make a living wage.

Scroll down to discover 13 examples of truly horrible tips. These restaurant workers are not being paid enough to deal with customers like this.

1. “Happy Mother’s Day”

2. Shared by a Customer

3. Ignored the Catcalling

4. Australian Accent Would Be Nice

5. “Call Me”

6. “Don’t Lie”

7. Thanks Anyway

8. No Tip

9. No Tip

10. False Hope

11. Less Than 5%

12. A Phone Number Is NOT A Tip

13. Play Money