I bought a couple of games from ebay once. I thought it would be the serial codes to input in the store, but the seller had me create a new Nintendo account and

I bought a couple of games from ebay once. I thought it would be the serial codes to input in the store, but the seller had me create a new Nintendo account and send him the name. They added funds to the account and bought the games themselves and told me to play from other accounts. Then I realized it might had been carding. The games downloaded and worked fine. After some weeks the bad account has an admiration sign in it's icon and I can't log into the store with it, but the games still work and even get updates. IIRC, the 3DS had the record of which games were bought tied to the console instead of the account, which made it easy for pirates to download the games once the console was jailbroken. It seems to be the same route for the Switch.