Originally Posted by
gary_nj
This was sort of hinted at earlier, but I think it also allows flights from Canadian airports to a lot of US airports that do not have customs and immigration facilities. One could argue that the same benefit should work the other direction, but I believe there are probably more "second-tier" cities (warranting transborder flights, but without immigration facilities) south of the border.
So true. Quite a few northern US cities might not be able to afford the whole customs setup, but by the preclearance they can handle a few trans-border commuter flights with no problem. No sense in paying all that money if your airport has 2 or 3 Horizon Dash 8s from Canada as your 'international' flight load.
I'd still like to see the US and Canada enter into a Schengen type agreement with regards to their border crossings.