When you go out to a restaurant and order food, you don't expect to have to go back into the kitchen and prepare the meal yourself. Of course you could do this on your own but the idea of a restaurant isn't that you just pay for the food. You pay for the service, quality and convenience.
All too often printers allow their customers to cook the meal instead of preparing it for them. Yes the customer may want options on design, stock and size just as anyone would expect a menu when going out to eat, but at the end of the day they work with a printer because of the service, quality and convenience they offer. Make printing easy. Easy is why customers work with you in the first place. If a customer wanted to print it themselves they would already be doing so (and quite possibly for much cheaper). Give them something worth paying for.