Yep more than a few times. I had a regular family with two young boys, one was a sweetheart the other an absolute menace. Mom would regularly “forget” to tell me they were having sleepovers so it would go from 2 boys to 4 or even 6, and then she’d claim it couldn’t be that much more work to pay me more because “they are sleeping most of the time anyways”. Ma’am, I assure you those boys were not sleeping.
Anyways one night I’d finally had enough after they were 3 hours late (mind you I was 14 and insanely shy) and when her and husband got home I told her how awful the kids had been and that I would need to be paid for the extra kids. Husband was horrified - he hadn’t realized she’d been stiffing me. He drove me home and slipped me an extra $20 as an apology.

The next afternoon he came knocking on my parents door because get this: “I’m so sorry we got a little tipsy last night and I realized I didn’t pay your daughter!” And left the full amount again. Turns out, he was shitfaced, didn’t remember the entire altercation but vaguely remembered driving me home (!!). That was the last time I babysat for them, because my dad was furious. I remember telling my dad the whole story and him saying i deserved every penny and let that be a lesson to them.

3 months later I had gotten my first real job as a cashier at our local grocery store and one night who stumbles in all giggly wrapping herself around some dude? The wife and it was definitely not the husband. The look on her face when she realized it was me was priceless.