Table manners are more important to some than they are to others. You know this if, as a kid, you ever went to someone else’s house and found out the hard way. Maybe in your home, you played things pretty fast and loose. You all ate on your own schedules, and you didn’t wait for anyone else. Then you go to your friend from 5th grade’s house after school, and you learn a whole other way that families can behave. This family all sat around the dinner table together. They all waited until everyone was served and seated before they started eating. Maybe they even said grace and held hands. This is all new to you. But how were you expected to know? Everyone grows up with a different set of expectations when it comes to manners. 

But it’s your job to be flexible with your own expectations. You don’t get to control everyone, and you don’t get to control how they present themselves. Especially if they’re a stranger, maybe you can quietly judge, but you certainly shouldn’t make it their problem.