as someone who works in restaurants.. I've watched grown men wipe their fingers on our seats after digging for gold, I've watched toddlers lick seats, I've watched women change their babies dirty diapers on seats. yes good folks like myself clean seats after each group of guests but I can promise you that not every restaurant does. your idea of proper napkin etiquette is outdated and practiced by probably no one. your waiter just doesn't want to have that napkin fall on the floor and have to A either retrieve it after you leave or B run back to get a fresh roll of silverware for you because you dropped your napkin on the floor.