[elai]

Higher Taxes. Quebec has generally higher taxes vs. the rest of canada, and places like washington have no state income tax. Also the locations it could be comparing could be downtown metro area's and their costs. 3km away from the downtown core and you get a huge drop in price.

[afterburner]

The taxes aren't that much higher. And the rent is cheaper than Toronto.

[teamonkey]

You're looking at approx 30% deducted at source for 50k in Quebec, I think. You get quite a lot for your tax dollars in Canada though.