captainsolo said:

This will usually will happen in historic and art house theaters when showing original prints and the like. You always have to make do with some slight cropping in some instances depending on the projector, screen, distance, or projectionist. The better the theater, the better the image. This kinda recalls the reasons why the THX certification was first introduced.

Last year I saw an original print of Get Carter that actually had image on the curtains like Zombie describes above.

The art house\historic theater angle was my first thought when I read the post. There is a 1930s-built theater here in town that shows old films regularly. Just sitting in there eying the screen, it looks to be VistaVision aspect ratio. Since it was built in the 30s, it was probably Academy ratio originally. They have curtains at the sides, as do most theaters, so they can alter the screen accordingly.

It's been a long time since I last saw a film there, but from what I can remember, the building doesn't seem like it could hold Cinemascope. If they showed Star Wars they would almost certainly have to crop it down the way the Senator theater did.

*edit*

Like Solo and Zombie, I've seen a few modern films incorrectly cropped to where they had image showing on the curtains or above\below the screen. It's not limited to old films or old theaters.