Have you ever watched a movie? Were you blown away by all the execs they added in the credits and assumed they must have had thousands of others under them not mentioned? Or do you not typically assume every other industry follows the same standard as yours?
What you said is akin to me saying "Why are they expecting their name on things? The restaurant I work at doesn't put my name on the menu when I'm cooking that night."
It's a different industry and I would be foolish to assume the standards in mine definitely should translate to others, and then confidently comment publicly about it.