Imagine the lawsuits if the train wasn't 100% stopped when the doors were opened.
I personally don't understand why it's done... but it is, and it seems common enough that if they were going to get sued they would have gotten sued.
Maybe Canada is a lot different than the US, though.
Montreal is just different than anywhere on the planet.
The only places in the EU that have public transportation on a scale comparable to NYC are London and Paris. I haven't ridden in Paris in a while, but in London, you absolutely do see cars that are overcrowded with people leaning against the doors.
Say what?