Imagine that in this other alien culture, most people were using credit cards for most transactions and rarely ever use their ATM/debit card. They don't have a day to day use for cash so do not frequent ATMs nor do they have much reason to frequent bank branches.

They've been presenting a credit card and making a squiggle with a pen for years and never remembered a PIN at all. Their credit card bill is paid electronically online somehow, either automatically because of a direct debit configuration setup years before or via an interactive banking website. These were authenticated with a web password and perhaps archaic knowledge of a routing number and checking account nunber. No PIN in sight there either...