Standby
Doubt it, from what I can remember the last 5 times I flew to toronto, Canada their was always empty seats whether 1 or 2 and sometimes 5-6 seats.
Lots of times I got bumped up to bulk head(would be stupid to pay $27 for an upgrade when I can wait till I board and get it for free.) and single seats all because of those that miss their flight or wasn't fully booked.