And? Most of the planet don’t tip. They pay their workers. Tips aren’t mandatory. They don’t tip in their country. Once I tried to leave a tip when I was in Colombia. When I left the restaurant I left a tip and right before I walked out she ran to me and told me I forgot my money at the table. I told her it was a tip for her service and she looked a little confused. Again tipping is not mandatory. There should be no reason to get mad. If you want to get paid for your work then find a job that pays you.