The idea is that you are there to be served, not babied. So yes, you are expected to flag them down. It is a signal that says you are willing to temporarily su

The idea is that you are there to be served, not babied. So yes, you are expected to flag them down. It is a signal that says you are willing to temporarily suspend your unassailable privacy. It is up to you to decide when to order and when you are done with your meal (if it's not too busy). If you want to read a book quietly at your table, nobody will make you leave. If you want to chat with your friends after the meal because you like sitting down where you are, nobody will bug you to buy a dessert (and conveniently up the gratuity). I can see how Americans may perceive it as rude, but to me it's an affirmation of personal space, both to the waiter that does not feel compelled to ask how things are going (always when I have a mouth full of food), and to the customer that can enjoy dining in peace.