Behodar:

 

Technically I think you could do it anyway, as I believe the moment money has changed hands (i.e. "Accepted" has appeared) then the transaction is complete and the goods are yours. Usually I would hang around and press No, and I'd even occasionally put the voucher in the bin, but sometimes I'd just walk away anyway.

 

I think they've also  flipped the time-out option to No,
Once you get the "do you want a receipt Yes/no"  there will be no receipt unless the consumer actively pushes "yes"