I use a Canon 5DIII, 5DII and 1D3 (among others) and always shoot simultaneous RAW and JPG. I see both files, side by side, whenever I open the directory in Finder. No idea what is happening with yours. When you select the RAW image, right click it, and your see your software options to open it. In my case, I may chose from DPP (Canon), AdobePhotoshop, or Drawberry. What do you have the default selection as? Apple Preview will not, of course, natively allow viewing of RAW images.