This is how it used to be.
If you have loose change in your pocket. When they break your big bills, if they want a tip, they better be smart to break that 20 down to ones and 5s. It is tipping industry service worker's hack that everyone of them should know by now. If the customer do not have loose change, what are they going to tip with?
Unless it is pay by card and you fill in that tip on the receipt portion.
My MN cousin is a big tipper because he doesn't know the rule. Free beer at them nevada casino and yet, he tips her like over $5 every freaking time. I was amazed but I finally got what he was doing. Tip big and them waitress lady will come back more often to keep your cup wet.
My atl family, they are big tipper. They do it because they do not want to loose face.
My worse experience with tipper is when I was a tad young and we were flying out of narleans airport. Kaydoo guy working for the airport be helping us taking our bags out and threw them into a conveyor belt. My uncle gave the kaydoo a $5 tip for his time. Now this was in the mid 80s so $5 holla was bigger than what it is today. The kaydoo had a crying face and told my uncle and I quote "oh come on man"
The mind of a young one is fresh. This is why we protect them from disturbing behaviors as it will put a lasting impression on them for the rest of their lives. I tip kaydoo poor because of that. I hate entitled people with a passion.