As a buyer, I should be able to get a refund if I’m unhappy about the project. EPIC could do a small amount of checking in the editor/launcher to make sure I don’t use a copy of the files, but even that isn’t strictly necessary. As long as there is no additional fee to you, the seller, for a refund, then a refund doesn’t hurt you. (Unless you count your dollars the very day someone buys something, which is a bad idea – count them when they actually hit your bank account!)
Overall, worrying about the 1% of people who will serially buy-and-refund and then try to use the content anyway, loses you sales from the 99% who will happily buy most content, and ask for a refund only if they are genuinely not helped by that content. Given the refund policies of PayPal, Amazon, and the likes (even for digital goods,) I think EPIC should be on that same bandwagon, because the additional business generated by having “no risk” policies for buyers, is bigger than the cost of issuing occasional refunds. If you can only “see” the refund costs, and don’t get excited by the additional business/sales generated by the policy, then you’re not a business person, and should probably leave the business decisions to those who are. (Or you can choose not to sell at all, that’s always available, too!)
Anyway:
Naming conventions: A good thing for a lot of people.
Refunds: Overall, a good thing for the marketplace and the sellers (EPIC should probably loosen up their policies!)
“Infinite Affordable Landscapes”: They are not infinite.