In the hope that this will only be a very brief change of subject, the answer is 'yes and no'. That is, plenty of tunes used in morris dancing have also been found in vernacular tradition in the USA (some, as you presumably know, having originated there); but not associated with morris dancing, which is a Revival phenomenon there. Specialised community traditions tend not to travel with migrants unless a significant number of members of that community migrate, and settle, together.

If you want to go into further detail, I'd suggest a separate thread so that this one can concentrate on its intended subject.