Assuming financial liability is an option, but because the risk profile of having an agent making purchases for a cardholder will never be zero, the companies making these guarantees will simply price the risk in to the cost of service. It’s the same basic mechanic at work with credit card reward points, the brands are all fighting each other for a share of customer debt so they slowly increase the rewards rates to one-up each other, and make up the cost on the back end by increasing merchant fees. It’s a dumb, unnecessary price war that ultimately increases the cost to the consumer and drives up the profits of the businesses providing risk/cost-burdened services.