Writing humor – funny only to writers?

I can’t quite explain why I find punctuation humor so incredibly funny. Perhaps it’s the comments on this site: The “Blog” of “Unnecessary” Quotation marks. Perhaps it’s because I often take unneeded quotation marks out of other people’s writing. Whatever the reason, I find blogs like these hilarious and laugh until I cry.

Is this unique to writers? Do you think writing humor is funny, too?