I also get basically a free appetizer lunch from Costco more or less every time I go. So even if I don't reap rewards over and above the cost of membership, free light lunch for two every Saturday when my mom and I go is worth it. Even a cheap burger each would cost $10+ for lunch for both of us.
If Loblaws included a random free package of something to try every time I shopped, this might be worth it.