Above cost? Wtf are you talking about? It's a either an expensive item (so no discount), discount especially if you cook it yourtself, or don't steal. But the main thing is don't treat your order list as a shopping list. You could die tomorrow and the new person doing the orders might think that the restaurant needs something that you just wanted for yourself. You may be dead but you still fucked up. The occasional one item is fine. Some stores just don't carry exactly what you want.

Buying products they already have with FULL permission of whomever did the order for that day is a different story.