My previous bank already offered this: for 5 bucks extra you could get your own image printer on your debit card. They are one of the most popular banks around here, yet I rarely see anyone with one.
I've seen it as well, but for me, it'd be better to have premade images, and Valve can make images that interest me and aren't too cringe.
It's not a massive business, but it's probably good side money since many banks offer it. It probably costs 5 cents to print on it, and you can easily get me to give you 2$ for it. Up to 5$ if I really like it or you catch me in a moment of weakness at 2 AM.
And they can probably try to make it a big business. They managed to get people to spend stupid money on skins, levelling Steam accounts, etc, so there are probably whales who'd collect cards. For example, if you get a special card skin unlock once you 100% a game, or you just add rarity to them. The chances aren't huge IMO, but I'd have never guessed people would pay the money they pay for skins and levels anyway, so..
