^I'd say that in business, "pure avarice" is an absolute necessity.
Well a really basic operational definition of a 'business' is "one or more persons coming together with a common view to making a profit", so excuse the pun, but profit is the bottom line.
The question of avarice in this context for high-end DSLRs is whether or not the net margins are as high as they are (in percentage terms) as say a Rebel body. IMHO I don't believe that Canon operates on a straight mark-up basis. My thoughts are that it is very calculated, just like automobile manufacturers use differential pricing in different markets, as well as differential relative pricing e.g. a 3-series BMW costs the same in most countries, but large deviations appear with the 5-series, then there is the 7-series... and that can cost more than 3 times the price of a 3-Series and easily more than double a 5-Series, but does it cost more than double to make. Of course not. Ask a main BMW dealer though how many 7-Series he's sold last month, then ask how many 3 or 5-series...and you'll quickly get the idea (just FYI in Ireland you can get a new 530d for fifty grand, but you'll pay 134,000 euros not dollars for a 730d).
Canon could easily drop the prices of the new 5D3 and 1DX to say $2,500 and $5,250 respectively and perhaps sell two to three times as many, but then they'd sell proportionately less Rebels and so on. Finally, they'd have a big problem selling lenses (at current prices) to people and this is where they must make a ton of money. I mean why does a T2i cost twice as much as an iPad3? Unlike Apple Inc., Canon Inc. are more interested in selling you the accessories like lenses, grips, sync cords, flashguns (all at high prices) than just selling you a single product.