In my experience, if you've been enjoying the pre-match discounts, had a pint at half-time, AND you're still in the stadium 90 minutes after the final whistle, you've long since lost the ability to make sophisticated purchase decisions based on whether or not you're going to save 35 pence.
Seems sensible to me, since a graduated scale of cash-back deals serves a wider purpose (encouraging a change in travel habits). And, by removing the incentive to use cards at half-time, they will be encouraging fans to be less selective about which queue they join - which can only help reduce...