The rumor suggests the building has trademark protection which prevents Disney from selling photos (photo pass) of guests with the building in the background. In a past thread a CM, or was it someone who knows a CM?, said Disney photographers are specifically told in their training not to take a picture of a guest with Graumanns Theater in the background.
There are some representations of the building registered as trademarks.
I'm aware of what the rumor suggests, and I'm telling you the rumor's basis is incorrect.
In a building built or designed post 1990, what you suggest about trademark or copyright would be perfectly valid. If it were built or designed post 1976, it would have limited protection.
Graumanns was built in 1926.
Disney can take, sell, and use, all the photos they want of the facade. They can even use them in promotional materials, if they want to.
I can't speak to rumors, or company rules. I can only tell you what the law says.
The law says: No copyright or trademark claims could be applied.
The only thing the owners of the theater could enforce would be the use of the actual NAME (Grauman's Chinese Theater or TCL Chinese Theater). But Disney doesn't use it. Not anywhere. Likely the representation of the facade you have seen copyrighted or trademarked involve the name being prominently displayed in the photo...thus, the trademark isn't of the facade, it's of the name. Which goes back to "you can add modifications or elements to the image to CREATE a trademark or copyrighted image".
That doesn't mean there isn't some OTHER reason Disney doesn't want to use the facade in promotional materials. But it's not copyright law or trademarks.
Here's another explanation (though the 1976 date reference in there isn't quite right...it was the beginning of the legislation, but it wasn't ultimately turned into hard restriction til 1990):
http://www.yesterland.com/removehat.html
In short, it's an urban legend.