They seem to have tried and given up in the US as well outside of an online presence. It's a pity, as they make 'ok' gear at good prices. It's perfect for if you're getting into a sport, or know you're going to use it only casually and don't want to spend a lot on high-end gear, but want to avoid getting something that's completely cheap junk.

They are still in lots of cities outside Toronto.

Are you sure? I spoke about decathlon in Canada with a friend of mine living there (Ottawa) and she says it’s there.