Even if you do everything you can to prevent it, you still incur refunds. It is simply impossible to get everything right 100% of the time - not in the least because people keep buying the wrong items. Things like cancelled or modified orders happen all the time, and you can't really do anything to prevent those.
And that sounds like the cost of doing business to me. For especially egregious cases the companies should reserve the right to charge customers for being stupid and wasteful.