Maybe they disappeared in Alberta for the same reason as the US...

http://www.texasgoldengirl.com/afterhours/strip-clubs-and-the-2-bill

>We don't see any around anymore either. Of course, we went with one and two dollar coins, but the province of Alberta pretty much got rid of two dollar bills many many years ago. They were still legal tender in Alberta, of course, but nobody wanted them. The inane reason was that they were considered to be bad luck. Maybe that's also why they started disappearing in the U.S.