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by ascagnel_ 67 days ago
Costco requires a membership, and they do store credit back at higher tiers. They absolutely know what every member buys.
2 comments

I suspect they're looking at the cost of implementing a one time refund/credit vs. reducing prices without the need to implement anything special.

Yes, I'm being charitable but not having to spend part of the refund on an extra program could benefit their customers more in the long run.

(We're Costco members.)

My point was that the other stores do, too. Or 90-ish %.
I remember a story on Walmart's data analysis capacity being something like 2 years of line item data for a customer. I've read numbers that suggest 10PB / day ingested from their ecommerce operations and 2-3 PB/hr data processing. Pretty incredible.
For modern ecommerce, figurative recording every twitch of your mouse in their store, I'd believe that.

But to save only the "SKU, qty., unit price, date" receipt info - which you would need to process tariff refunds - that'd be maybe 16 bytes per receipt line? To hit even 1TB/day, you'd need a billion customers, each buying 64 items. On that one day.