Here's the behind the scenes video (text from youtube video description):
We speak to Martha Delap, the director of the television series and a few other people involved behind the scenes.
Note that about 2:27 into the clip, one of the Canon EOS 5D Mark II camera men, Paul Gwilliams, is interviewed and he describes that their main cameras are Reds but that they're using the HDSLRs for pickup shots, food presentation, etc. – ‘we're getting the shots that Red cameras maybe can't get – top shots of the the table' etc.
Here's a snippet of the video giving an example of what the camera man, Paul, is talking about:
(Photo credit: snap from the video)