I wouldn't repeatedly not tip just to avoid having my food tampered with, but if it's a one time order and you won't be dealing with the same person again, I see nothing wrong with not paying some nebulous amount you never agreed or were asked to pay.

Agreed with this but you have to wonder: if the “delivery fee” is not paid to the driver, and there is truly no additional work to prepare a delivery order than a pickup or dine in order, then .... ??