Originally Posted by WhiteYUL

Here's to clarify, if you book through Aeroplan (AE, as it is regularly referred to on FT) and flying on AC metal you will get dinged for high fees, mostly YQ (fuel surcharge). However, if you book through Aeroplan on a handful of other Star carriers, e.g. UA, you will see much lower fees. This applies to international (e.g TATL, TPAC) flying. North American flying doesn't have such YQ charges added.

Now, if you pick the same AC flight through UA, it'll cost $117 (in Y).

AE = Aeroplan miles, to answer your second question.