If the bid is to old or whatever and does not go through it does not affect the round. Furthermore, a refund on that type of bid does not, after the fact come out of your pocket. It comes out of the pocket of the person you wont refund it back to. In my opinion, user error or not this is shady business plain and simple. With the price of sbd what it is currently and the fact that you likely pay in steem like most people for your delegation we all know you are making plenty enough to offer refunds when mistakes are made. Anything short is stealing.