Big orders require pre-payment. If no stock is available the customer should expect a wait. Even a pizza shop will require a credit card for 20 pizzas.

If someone is selling 1 million dollars worth of widgets and the buyer is unknown prepayment is required. If known and a valid purchase order is signed the customer usually has net30/60 to pay if they don't there might be a lawsuit or a black mark on their credit file with collectors calling.

Does it ever make sense to pay hundreds to win that 2 dollars back? Your employees waste more when meals don't turn out perfect. The cost of food to the restaurant includes the wasted food (usually from employee mistakes) and those are reflected in the prices.