I'll actually say with the OP that I think this service has a convenience factor if you've already got a 99 cent iCloud subscription, or if you value your time more than the effort to go through your sock drawer and then buy $1 amazon giftcards (which you can't even do reloads of $1 on Amazon anymore) to keep cards active.

The argument on minimum transactions to get rewards or avoid an account monthly fee... eh. I don't think the math works on that one.

By the way OP, saying this legitimately, generally it is against the terms of your merchant acquirer and the network to use your own debit/credit card at your own business, because it's an easy way to avoid cash advance fees (versus much lower swipe fees). If you are using this service to charge your own cards, I would stop immediately.