I think it should work like this:
You need to purchase the virtues in order to:
1) Trade an epic to another player
2) Auction an epic
3) Equip an epic
You do not need to purchase the virtues in order to:
1) Receive an epic in a trade from another player
2) Buy an epic from auction
Because almost immediately after I found out Decker had the epic, I wanted to borrow it from him just to purchase the virtues. I can't do that and that's cash you're missing out on Jeff.
