I liked JohnInKansas' phrase 'emulating the ego of the superstars'.
I've observed one or two people doing this over the years in the world of folk and, yes, it often does go along with ambitions over and above the abilities of the person with the ego (or, as we succinctly put it around here, the one with the 'ead as big as Birkenhead').
There are, in my experience, generous performers and selfish ones; those who relish others' successes and those who,sadly, consider their own success the only worthwhile goal.
I think there's a difference between confidence and ego, particularly when it comes to entertainment.
However,I'm fortunate at the moment to be working with a lot of people of the generous persuasion.