>if you overshot (asked for 50, used 46) they refunded the difference in cash.
I never seen that. What I always saw was they authorize for $50, then charge $46. If they're doing how you described it, they're paying interchange on the extra and not getting anything for it.
This was someplace very rural, maybe the cost to upgrade systems was more? This was also pre chip-and-signature, I haven't had the issue since the switch as long as I can enter my ZIP code on the pump.
The Authorise / Charge thing has been around for a long time - it's the same thing that hotels do when you check in. I'm reasonably sure that all terminals have the feature.
It does, however, require that the machine operator is aware of how to do those operations - it's probably easier for them to just charge the card for the set amount, and refund in cash.
Though this slightly increases their risk, as any chargebacks means not only do they lose the product, but the cash too.
I never seen that. What I always saw was they authorize for $50, then charge $46. If they're doing how you described it, they're paying interchange on the extra and not getting anything for it.