I had another delayed flight and recieved 8 vouchers. I first went to load it to my Starbucks app - but the app would not let me change the country of the billing address, so I immediately went to to the Tim Horton's in the Calgary Airport at 12:55 am (one of the few places that was open at that hour) and tried to use them. The first voucher failed, so I tried the second voucher they gave me and that worked. So I went and used the third voucher and that failed, but the fourth one worked! So just to let people know, not all of the vouchers work - or at least a couple of them don't work. As well not sure where the change country on the app for billing address is. I did manage to add vouchers 4,5,6 to the Tim Horton's app and then it failed to load.
Further, my daughter was flying Air Canada that night, so I texted her vouchers and when she arrived in Montreal about 10 hours after our delay she went to Starbucks to use in the airport at YUL and the clerk had never heard of Westjet and their scanner would not accept the voucher, so I had her try at the Pork and Pickle and they also said they had never heard of Westjet nor seen one of those vouchers. So unfortunately voucher 7 and 8 didn't work either at YUL or at any locations she was able to find.
It's unfortunate the vouchers are coded with a USA zip code, as well it's unfortunate that some do not work, and it's unfortunate that so many airport locations will not accept them, and it's unfortunate that they expire a few hours after they are given.