You can buy a $50 Gift Card to The Keg and get 20% off a $50 Roots Gift Card. So, totally 10% off for $100 Gift Cards.
Besides, you can also earn 10X Air Miles at airmilesshops.ca until Jan 5, 2017. This is about 5% cash back. Please see details: http://www.canadianrewards.net/2016/12/air-miles-shops-10x-miles.html