I won a 50$ gift card last week, it was a PITA to claim it.
First you need to tear up not only the "Win a 50$ gift card", there's also a 8 or 9 digits code about an inch away from "Win a 50$ gift card".
I really didn't know about it and it seems like it's written in the contest rules (in lettering size of about 1 or 2)
Once I came back with the digit code (I was lucky the maid didn't emptied the garbages that night), they can't do shit for me since there was no manager on site to fulfill the required paperwork.
I did come back twice to that Tim Horton (which is where I got the winning cup from) and still no manager. They couldn't give me a precise time to come back since the manager run around 3 locations and doesn't have a precise schedule (wow.)
I finally gave a try to a complete other location where there was a manager on site and finally got the card after a super duper mathematical equation I had to solve.