Walk left, stand right. A rule I learned on the escalators in Toronto’s subways that holds as true in the airports I’ve passed through, in the US and Canada.
What I have found, especially at Toronto Pearson, but Calgary demonstrates this too, is that huge family/business/friends groups don’t always understand “walk left, stand right,” and totally block the moving walkway. If I’m heading for such a walkway, and I see a big group getting on one, I’ll avoid it. Walking quickly on the floor, I’ll often get to the end of the walkway before the group can ride there.