Sorry to resurrect this, but I noticed this too while I was on set of a film shooting with the Cooke Anamorphics. I can't believe people aren't up in arms about the ridiculous pincushion distortion on these lenses. It's normal for wide angle anamorphics to have distortions, but usually it's distorting the other way, i.e. straight lines are bowed inward. In this case they're bowed outward, to me it's just awful. I guess you can slap the Cooke label on anything and everyone loves it.
Well, I actually just signed up so I can comment and let you know that there's a glaring flub here in saying that "The Hateful Eight" was shot with 35mm cameras. Please fix that to 65mm cameras, don't want anyone getting wrong idea. THANKS!!!