"It's a credi- er, debit card. In my world, we keep most of our money in electronic accounts, and... this thing is sort of a standardized way of controlling access to... I use it to pay for things. You have orbs that atomize and contain superpowered monsters, and you're thrown by credit cards?"

As an aside, he asks the bar if Milliways has compatible power outlets- he's going to want to take notes on his laptop, and it's low on battery.