"Let's not forget that sometimes it's pure egotism that makes some people sing a long song. They want to be the center of attention for as long as possible."

Oh yes! That's so very, very, very, ... very true!

It was me wot complained about shanty singers in another thread - some of them seem to learn every verse that they can find, mainly, I suspect, so that they can "be the center of attention for as long as possible."