Honestly not sure if you are serious or not. Maybe they found one, if i could pay with only the numbers, so could they.
Or the parents card, scammed one, stole one or bought or traded one from someone that have stolen / scammed / found one for cash ... There were 1.036 million reports of identity theft in 2023 and the U.S. Federal Trade Commission reported $8.8 billion where lost by consumers due to credit card fraud ... they all came from somewhere ...
Yeah ...from the website
"All transactions are 100% discreet. No adult information will appear on your statement."
Now imagine the kid looking over at his parents with huge puppy dog eyes "Sorry mom, i just really wanted the game, and it was only on sale on Steam today, i`ll pay you back, i really, really promise"