Last time I was in Montreal my Uber driver wouldn't drop me at the airport, instead he dropped me at a hotel attached to the airport - he told me reason being in Montreal undercover police officers have been known to wait in the departures drop-off area and impound cars if they suspect you to be an Uber driver.
Interesting side note the driver actually was an airport employee - he would drive for Uber twice a day, once to work (he would hang out by the area of the city with lots of Hotels to try and catch and airport trip) and once on the way home. I thought that was kind of awesome.