I think what I was meaning was the true cinema crowd...feature films and whatnot shot on Alexa, Varicam and even Red, (which has generally supported the EF mount mores than the others). Rental price doesn't really factor into their equation, and not having a PL mount for all these years, has generally kept these lenses off of a lot of shows, unlike Canon's Cine zooms, which have a PL option, and are very popular. Even last years launch film for the c700 FF used mostly lenses from other manufacturers (canon made a point to mention during the demo that this camera worked with many of the lenses high end DP's are used to from vintage Cooke, to Leica, Zeiss et al) and I think the only canon prime they used was the 20mm that was launched at the same time.
Full frame is another story. Now that it's becoming more popular on the camera side and there aren't a lot of (reasonable) FF lenses on the market. Canon is in a unique position. I've always said that Canon has a leg up in the FF market, and its surprising that they don't exploit it. The fact that they were about the last to market with a full frame sensor camera is typical Canon, made more obvious by the fact that they had the foresight on the lens side to make these lenses FF when they didn't have a camera for it. (unless you count the 1DC or their still cameras).
Like I said, I own a set of these lenses, and I use them on a lot of projects. They are sharp, and have a clean, neutral look. Like you said, compared to a lot of the glass out there they are lightweight and therefore popular on smaller productions, and in situation where small is needed. I don't really hear high end DP's talking about them in the same breath as Cooke and Zeiss though.