Oh I do understand. What's more it's just as bad if they do it less well than you, or use a special song in a less appropriate way. I have been singing some songs for over 50 years - from the time when it was harder to find them. You couldn't just type a few words into a search engine, or put on a cheap CD, and BINGO. I always seek out all the information about the songs I sing, down to the situations in which they were born if possible. I don't sing songs that I can't relate to. I learned "Hard Times Come Again no More", among other Stephen Foster songs, from my father. It was just after the depression and he knew about hard times. Now I hear it sung at folk festivals as a jolly little sing-a-long with flashy instrumental breaks and it makes me so sad. We know that we can't own songs but it's painful all the same. Our ancestors had the problem solved. Sing-a-rounds were very carefully controlled so that singers had "their songs" that no one else sang. Field recordings often have remarks like, "That was Auntie Elsie's song, I never learned that one!"