The solo artist gets to call the shots. It is their name on the poster so understandably it is their call what goes on the poster.
For the duo: we did it your way last time so this time we are doing it my way. Makes sense. 50/50. If one person has gotten their way a bunch it is understandable to balance it out.
As for the band [anything with three or more], it gets completely different. Who is on whose side at this particular crossroads on this day and at this time? He always sides with you unless you agree with me and then all three of them are against us.
In a band it is too hard to keep track of “even” or how many times each person or combination of people have gotten their way.
The more people the more mess.
But the shared journey and fulfilment is the ultimate prize if you keep it together as a band.
PS: If you are not in music but you have watched how functional partnerships or families operate or children try and share toys…it is the same thing