There was a piece on GlobalTV on Monday June 10th about how many West Islanders avoid most of the summer activities in downtown Montreal, because public transport is not so reliable. Since actual Fringe show attendance is flat, this may explain why expansion hasn't happened. If people don't come from the West Island, then that's a big chunk of potential audience that we won't see.
I've noticed the issue, it would be fun to take a train out that way, but they are focused on commuters, so the timing is wrong if you're going in the reverse. There are some used book sales that open on a weekday, and I've not bothered because I've wondered about getting back after dark. The less frequent buses are, the less likely one is going to count on them. When Alan the volunteer gave up his car, his Fringe-going was badly reduced, he had to leave about 11 or 12pm to get back to the southshore before public transit shut down, or was drastically reduced. He ended up finishing his shift, and not going to shows. I don't even count on the bus when going home, I'd love to be able to ride home each day of the Fringe, but unless I follow the schedule, invariably it's a half hour wait for the bus, and I can almost get home in that time (well get most of the way along Sherbrooke).
This may be something that needs working on, that flat 20,500 or so attending indoor shows isn't changing, the only way to increase it is hard work to reach the people who don't think the Fringe if for them.