Those other options aren't always as easy to execute for everyone as you might think. Marketing, web site building, video editing, tour scheduling, public relations, accounting, etc.
That stuff is hard work and you have to be a jack of all trades. Each band is like a little startup looking for a technical cofounder.
This. Is exactly how it works. A first-time startup gets worse terms then an established entrepreneur, right? A first-time band is the same way. You do well with your first venture, you get better terms the next time. The indie film industry is very much the same way with distribution rights.
That stuff is hard work and you have to be a jack of all trades. Each band is like a little startup looking for a technical cofounder.