It can be quite eductional. Back when I was about 9 or 10 years old the absolutely first "Irish?" "trad?" tune I ever "learned" the melody to was a commercial jingle for the "Henry J" automobile.

Of course I didn't really know that it was a trad tune until about fifty years later, when I played it (by accident) from a collection book.

As to "spoiling" things, it does indeed conjure up a "vision" of that incredibly ugly little car every time I hear (or play) the tune.

John