What prevents Canadian retailers from buying direct from the same sources that Jenson and CRC buy from?
Volume and capital.
CRC does purchase some brands from their local distributor just like regular retail shops do. In order to be ultra competitive they sell at almost zero margin on these. Hard for a local shop to compete with a very well capitalized organization that is willing to blend all of their margins and work off volume.
I suspect CRC is also taking advantage of some OEM loop holes, jumping on any closeout offers, and trying to circumvent distributors at any chance. Low margins on high volume.
Smart local retail shops are likely trying to do what they can on a small scale. A really smart shop would be heading to Taiwan for the Taipei bike show instead of going to Interbike and bro brahing in Vegas.