[Quitelargegenitalman]

It seems to be just a barcode, nothing special about it, the barcode is the same on every voucher I received, I got the vouchers for complaining yeah, I bought some crisps (chips if you are american) and the whole container of crisps (chips) were completely crushed so I complained as I was a bit annoyed about it.

So is it just subtracting a certain dollar amount from the total?

Yes. It’s just taking a set amount of the transaction amount. On the T&Cs of the voucher it says it’s only valid on their products but I plan to try it tomorrow on something else to see if that is true

Very interesting, lots of potential for abuse, even more interesting if you can scan it multiple times..