AMS is just an example , other cities may also be needed.
So for instance , If I needed YUL-AMS , I would use Flight pass for Yul-FRA or BRU. Then do either train or low cost carrier etc?
Easiest example. Go to BRU and take the train, it not far really. Maybe a bit over an hour. FRA is much farther. LHR, you need to fly.
Real problem starts if you are going to MAD or LIS or ATH. Or further east, WAW. I have taken the train from FRA to WAW too...