This has been a source of professional frustration to me. I find it stressful to have to make decisions every time on how to set things up for the two different product teams I work on in my current job. When I push for common processes and procedures, I hear "do whatever works for the other people you are working with", which leads to a pastiche of different ways of setting up files, different ways of presenting results.
I wonder if it's a function of designers who've come from a graphic design-studio background who are accustomed to working individually, and sending their work off to a printer. That's what I did in the first part of my design career, but I don't think this "whatever" approach works well with digital product teams.