Interesting thread. I have done a little collecting, mostly by happenstance. When I heard a variant of a song, I taped it and ran off to taunt Kenny Goldstein. If he hadn't encountered that version, he added the tape to his enormous collection and, outside of asking who the performer was, no questions were asked. He didn't even buy me shampoo.
While we are on the subject, can we discuss the legal/ethical aspects of parody? I have written hundreds of parodies, some as mass colaborations. It is possible that Dick has written a few, himself.
Who owns them? Who owns my takeoff on Cole Porter's "Let's Do It"?
Who owns Dick's logical extension of Bill Staines's "Roseville Fair"?
How about the dozens of verses I have added to "Old Time Religion"?
When I was at Shriners Hospital, on a grant from the Philadelphia Folk Festival, the kids and I wrote special verse for that old army grouse, "Gee, Mom, I Want To Go Home". Who owns that?
Maybe, we should check with Saul Broudy. He does a program of chopper pilot songs from Viet Nam, where he served as a laundry and payroll officer (I kid you, not) and, although he has a doctorate in folklore, he may still have some rational thoughts on the matter.