The Bach cello suites, along with lots of folk tunes, do have chords but they are played one note after the other rather than all the notes at the same time. Sometimes chords are implied but quite often they are actually there, just sort of spread out. I had a big long argument with someone on the Session once who insisted that tunes did not have harmonies inside them. I could understand the objection to guitars knocking out chords all the time. I too prefer to hear just the melody, but those internal chords are there.