For what its worth there is a type of person who must have the very latest camera and will pay a high pre-order price to own the first ones that come in to stock.
Usually before the reliable review folks have given an opinion on them.
Usually with buggy early firmware.
But hey, they are the star of the camera club for a week. So it's worth it.
Canon will get stock out as soon as they can. Do they want to flood one market then move onto the next, or do they want to roll out stock to all regions at once? The latter makes more sense, certainly in terms of getting the cameras into the hands of reviewers and the unpaid beta testers.
So I think, with no inside knowledge, that they ship as many as they can, to as wide a spread as they can as soon as they can.
The nature of mass production is that they are not going to have enough stock to satisfy everybody initially, so those who are willing to pay the high pre-order price get the first stock.
I think its just the nature of supply and demand. Canon are no worse and no better than anybody else.
Consumers get it into their heads that the 70D is the answer to all of their photographic needs. Folk will coo at it for a week at the camera club and everybody is happy.
Especially me, who'll wait 6 months, see how the reviews are, see what FW fixes come out, get it grey for 2/3rds of the pre-order price.