I hope you bought it! Even if you don't want it for your collection, you could make somebody here on the forum very happy (or make quite a few maple leafs for yourself.) No, probably not a common occurrence any longer (at least not down here in the States.) It has probably been there on the shelf, and at that price, for years. I usually check my local stores like BB just in case something like that might happen. Kudos to you!
Also, I hear your BB stores North of the border tend to get various SACDs and DVDAs mixed in with the bargain bin from time to time...I would keep an eye out there too.