Sure. Not a problem. Watch out for the currency conversion markup on the credit card.

As mentioned, the Air Travellers Security Charge does not apply to tickets issued in the US (in USD) for domestic Canada travel.

The trade off for this is that, domestic Canada flights are taxed like a domestic US flight. The US Transportation tax (7.5% of base fare) and the US segment tax apply to domestic Canada flights for tickets issued in the US. These are the same taxes that recently expired and have since been reinstated.

However, those US taxes only apply within a 225 mile "buffer zone" of the US border. That covers most domestic Canada travel, but would exclude travel to/from YEG.

YEG-Canada has the best of both worlds when bought in the US: no Canadian security charge, and no US taxes either.