Interesting read. My friend, who worked as a roadie and tech for rock and metal bands, in the 1990s and 2000s, had some interesting stories about rock star egos and life on the road. Axl Rose of Guns n Roses fame was one such character with an ego with a capital 'E', others like Slash, the guitarist, was a down to earth person.
Some were and are very professional groups who are in it for the business and solely for the business. They hardly ever talk to each other outside of the staged interactions while doing shows and soundchecks.