But Don, I would not go to a Folk section and look for the Ramones.

"Folk" is not a great identifier - except to those who grew up in the folk revival and have a distinct image. Even then, I would bet that Conrad and Don would have a different definition of "folk".   

There is plenty of room under the umbrella.

"Folk" is a word with the same characterestics as the word "encyclopedia" - neither word defines the contents other than that fact that both are collection of lots of subjects, lots of entries, always something new being added. No one is ripping out the old pages.