The most beautiful tone comes from the harmonica when you play a simple single note melody. And with a little more practice you can make your instrument express the emotions of those words. You cannot do this if you try to fancy it up with difficult riffs and licks. I have heard harmonica players that were so good that their improvisations actually hindered my ability to even recognize the song. All their efforts to impress me were self defeating.
Music is an exquisite vehicle meant to carry only the most honorable of messages.
It should not be cheapened by carrying silly songs. I took my garbage to our local waste disposal site a few weeks ago and parked next to a classic Cadillac. I was shocked to see a lady get out and reach in the back seat for a couple garbage bags of trash. Apparently she had no respect for her vehicle. That is the way it is with many musicians.