This is how 1:85 is done, you shoot full frame, then block part of the frame when you project it. When you transfer to home video/TV, you have the option of using only the portion of the image show in the theater, or opening up and showing the whole frame.
How can a full frame be "chopped"?
I've seen it on lots of 'supposed' widescreen 1:85 DVD's, the original release of A Fish Called Wanda comes to mind.
They take a fullframe pic lazily created by taking pic off the sides to make it square for TV. Then they come along later on this same print and lay black bars across the top and bottom and call it 1:85. You'll know when you see it because the black bar on the top falls across everyone's forehead for the entire film. Looks like an extreme close up and looks very awkward.
I thought that was in the early days of DVD when the studios were being kind of cheap, reusing old transfers from VHS. Is it still happening?
It's in anamorphic widescreen.