I think the more appropriate term is "casual". because free use sounds kinda dumb and ambiguous.
specific kind of "free use" will be "casual rape". if a woman does not want it but nobody cares

also, casual rape is like extremely different from the plain causal world where nobody cares about that issue at all. This is very different kind of fetish and will confuse everyone

Of course, this does not mean that you should not post those "free use stories" But I would suggest not to use that term without explanation