It's a brutal, cold slap-across-the-face wakeup call, isn't it?
I'm amazed that AC/Aeroplan hasn't been sued yet. I know the lawsuit wouldn't win, but the differences between the two programs are night and day.
Millercorona - to answer your questions:
1/ no - if you have Aeroplan miles, you have Aeroplan miles. Period. Sorry. You'd do better to burn them up on United flights if you don't mind connecting through the USA.
2/ The reason they charge more is because they can. They're referred to around here as scamcharges for a reason. It's disgusting, I agree.
3/ There's a reason this Canadian uses Mileage Plus as his FF program, although most of my travel is to the USA so it also makes sense.