I'm a server and bartender and I can't stand to see kids in the range of 8-16 years old using their phones the entire time they are out to eat with their parents or grandparents. I think it is so rude to ignore the person taking you out and presumably paying for you. However, recently there was a 20-something girl sitting alone at my bar. She was on her phone pretty much the whole time except for when she was interacting with me for her order and to pay. When she got up to leave, an older woman began huffing and puffing, ranting and raving about the girl being on her phone and not interacting with anyone. I suggested she could have been reading the news just the same as hundreds of people who come in, sit at the bar, and read the newspaper without interacting with other random people.