The thing that’s been a real hit has been team-play games - League of Legends and DOTA 2 are both 5v5. Other games like Starcraft 2 and various fighting games do well as 1v1 competitions but sports games really haven’t caught on as much as you thought they would.
I think this is just something along the lines of the party-type events put on by the teams. It gives fans something fun to do during the festivities, and it will hopefully appeal to a younger demographic and give them another reason to keep returning to Grey Cup weeks.