I would agree that this is not enough.
However consider yourself luky that you did not get stuck on board.

At Xmas, was on YUL-CDG and we waited on the plane for 4 hours before taking off. Freezing rain storm which shut down YUL.
What did we get in 4 hours? A glass of water. That's it.
Plane was 767-200 and was sold as Y only!
So I would have taken the $12 or $15 any time. It also meant that you were in the terminal not on the plane... Lucky you.