Payment at restaurants in the United States is very different than you might be imagining. The process goes like this: * Server brings bill, disappears to go s

Payment at restaurants in the United States is very different than you might be imagining. The process goes like this: * Server brings bill, disappears to go serve others * Patron places credit card in the sleeve thing the bill came in, leaves it on the table, waits. (Maybe is still finishing a drink or dessert at this point.) * Server picks it up at some point, takes it to a register, swipes it (not in view of the patron). There is no entering of a PIN, because U.S. credit cards do not require a PIN. * Server brings receipt back to patron. There are at least two copies: "Merchant copy" and "customer copy". Each has two blank lines: One that says "Tip", and one that says "Total". Often a range of "suggested" tips is provided below. The "Merchant copy" also has a line for a signature. * Patron fills out "Merchant copy" with their desired tip, and does the math to fill out the total. Signs the signature line. Takes "Customer copy" with them, leaves "Merchant copy" in the sleeve, and exits the restaurant. * Server takes "Merchant copy" and puts it in the stack designated for such things. * At some point that day, a restaurant employee goes through the stack of "Merchant copy" receipts and enters the tip amounts for each one into the register. It's an insane system that beggars belief for people who aren't aware of it. But this is how it works at probably more than 95% of "sit-down restaurants" I've eaten at in the U.S.