You are missing the point by a very long way. The jazz musicians who adopted Broadway showtunes in the middle of the 20th century instead of what they were doing before were mostly black and working class, and suddenly they were playing white middle-class music instead of their own. Showtunes are no sort of folk music for anybody, by even the most lenient categorization. And the way the jazzers treated them showed absolutely zero respect for them. Understandably - they didn't deserve that respect, and jazz got wonderful results by utterly ignoring whatever the tunes were actually saying.

Kenneth Rexroth has some interesting things to say about this:
http://www.bopsecrets.org/rexroth/jazz.htm

I don't know what Cole Porter or Rodgers & Hart thought about what the bebop generation did to their music. I imagine they were outraged.

A jazz musician today, coming to traditional music with a condescending attitude like "it's all based around 5 notes", is if anything, showing even greater hostility to their raw material. At least the bebop generation took the trouble to understand the musical structures of the showtunes before disembowelling them. Seems like you care nothing for either what the tunes express or how they came to be. And you expect us to listen to you?

Take a look at the modes tutorial on my website:
www.campin.me.uk/Music/Modes/

Some of it's based around five notes. Most of it isn't, and whether it is or not, there is a great deal more than just that going on.