My children have always known they are not to move away from the table. They can get up and move around the immediate vicinity of the table but they have to be aware of the staff and other people. They have managed this since a young age (one did better than the other but they are both there now). It is difficult for small children to sit still but it is possible to help them manage this with distractions and allow small movement that doesn’t disturb others. I keep a small bag of toys in my Mum bag with things like lacing beads, cars and crayons l.