Good thoughts as always, ol' pal.
I think one of the sticking points that some have is a matter of who created the "loop". If it's their own creation it's OK, but if it's a purchase... not so much. Not that I personally see a big difference between a store bought loop and having someone else play something which you later edit and, uh, loop.
Then there are those that simply play everything live, all the time, and don't loop anything in any fashion. Old skool, and certainly nothing wrong with that.
Then there's that middle ground which you described so well... Though I would venture to say that since you played in the parts, what you do with them afterwards is simply not the same as selecting from a list of preformatted clips to create a piece. To some people, that is. I don't happen to be one of them since I do use loops and like 'em, but there it is...