Hacker News Reader

Based on the intonation, I'm guessing it's a "loyalty" card - it tracks your purchases, unlocks some level of default discounts, and will often accrue points you can then use for various purposes. Giant Eagle in the US is a good example - you earn points for every dollar spent, then you can redeem the points for percent off gas at their gas station, a percent off coupon, etc.

(the above description is very bland - add in anti-capitalist/m messaging wherever you deem appropriate, I won't argue)

Some store chains still have their own credit cards that aren't just co-branded. Far less common these days but I've still occasionally signed up for discounts on large purchases.

> What is a store card in that case, and how does it differ from credit card (other than, I assume, the place you apply)?

It's not a credit card, debit card, or any other kind of payment card. It's not even, like, a COSTCO membership card.

It's a tracking card that is used by the store to track your purchases in exchange for a small discount on some items if you swipe it at checkout.

Thank you, and that does seem like a ridiculous thing for which to request an SSN.