Yes, I take your point about the issue of returned tickets going unsold. Reflecting on the current season however, I'm very confident that a scheme similar to what I describe would have generated significant income for the club (particularly when a £2.50 child credit for a seat can be re-sold for £28) and increased the actual number of people inside the ground. Of course, should future demand fall, then there's a risk that returned tickets go unsold. However, given the credit should be in the form of vouchers to be spent within the club, the risk feels low to me.I can see the logic in that.
What doesn't work for me with this is that it's a refund irrespective of whether that particular ticket is resold.
It's particularly hard to track as regards to Big Bank tickets which is why I suggest a one-off calculation at season's end.