So I cleaned this up for you. 

It certainly has its value to add the  history of these places but should be done with an adequate sense of rigor.

demolished=yes was introduced earlier. That wasn't great but at least it still had the main campsite-tag, so it did make sense back then.

demolished is of course a supported prefix for anything that can be physically demolished like a building. How can one demolish a name ?

It is never a good idea to put websites without checking them, in particular, not in this area.

Anyways, should be fine now! Let's hope some of these places will be reopened eventually.