It's been a long time but when my husband and I would take our 3 daughters to Canada and wanted to just walk through the casino we were blocked from doing it.
The guard (or whoever it was) told us they had to 21 years old to walk through there. It was somewhere near the late 90's I believe.
Maybe Canada is different, maybe they've changed the rules. I do know we weren't allowed to even walk through there. We had to find another way to get to where we wanted to go (which I don't remember where it was then).