The location of the site is pretty pointless and impossible to obscure (everyone can find it in satellite imagery). However they can certainly obscure more specific details about the site: what building houses what, where access points are, physical security measures around those points, components used in entries, etc.

I'm guessing here because they don't tell you.

But at the gate you couldn't see much of anything. So you effectively never saw the outside of the site, and even parts of the inside of the building.

What you could see, where you could go, all of it seemed to be clearly planned ahead of time and it was just what was essential to complete the task.

Not op, but if there are multiple buildings you won't be able to leak which one is working on what.

Everyone knows roughly where Area 51 is, but that doesn't necessarily mean they'll let a contractor know where all the external security cameras are sited.

If "the site" was a building on a military base you'll still have no idea where the exact location is.

I am guessing to obscure which building was which since the blind fold didn't come off until you were inside the building.