That's why some people think the copyright length has become too long and some are wanting it changed. I can understand your thinking Clifton. This is one of the reasons why publishers stopped taking unsolicited material in order not to be accused of infringement. Now with the internet overflowing with songs it seems even more likely that similar melodies are going to occur naturally or on purpose. But unless a song is a hit - possible but highly unlikely - copyright cases are too expensive for most people to pursue.

I don't believe most songwriters set out to steal. Most times it's just laziness and going with the first thing that pops in their heads which is more often than not another song they've heard. And in coming up with melodies it's not just the notes, there's also the rhythm patterns that can be changed up. It takes a focused effort to write original melodies because if you stray too far off the familiar people won't like it. So the challenge is keeping it somewhat familiar while making it different enough. My two cents.