They probably don't and it's just for pricing and printing receipts...

I guess they could record the sales using carbon copy receipt paper.

Realistically it only needs to hold info for the day. It's a bakery. They just need to know how much money should be in the cash drawer.

They make user port carts with SD cards that basically function as hard drives these days (though I doubt they would be using them). There is also paper as a record which may meet any requirements they have.