i think you have been over charged. did you ask for receipt? whenever i pay, i ask for receipt. the caterer says~okay, pls pay and i ll bring the receipt and he never returns. so now i politely say to them that i wont jump off the running train. please do bring the receipt and then take the money. also getting a receipt provides you with an option of genuinety of the caterer, quality of food, option to complain or give a feedback when you reach the destination. without receipt one can do nothing...