Given the assertion ' Most menu prices include taxes and a service charge, but it's customary to leave a tip if you were served satisfactorily.', does 'Prices on the menu include taxes, but customers decide whether or not to tip.' offer a contrary position?
 Most menu prices include taxes and a service charge, but it's customary to leave a tip if you were served satisfactorily.###Prices on the menu include taxes, but customers decide whether or not to tip.