Fixing first components

I wanted to start a discussion about the Advantages and disadvantages of Fixing components and, more specifically, if there's anyone who doesn't.

I typically fix a component (Part/Sub-assembly) in every assembly - usually the component that everything is built around or that would be fastened to the ground. I've just stumbled across an assembly where Fixing may not be ideal and I'd actually like to keep a space between the Floor and components; primarily because what would be touching the Floor in this case would be a few bolt heads which I don't particularly want to fix. This space may Change in the future depending on bolt head size, therefore no Fixing, just mating to the origin planes.

Is there anyone out there that never fixes components and always mates to the planes?

Is there anyone who fixes everything in assemblies and never uses mates?

Is there anyone who would alwys fix one component no matter what (what I expect is the norm)

I am curious and would like to know

SolidworksModeling And Assemblies