Fair in the sense OP is using it is in the moral sense, not the economic sense. Paying someone tens of millions of dollars when the lowest paid workers in that company make ten bucks an hour may be "fair" in the economic sense, in that it's what the market will bear, but I don't think it is any way fair in a moral sense.
I think too often people let the "morals" of the market replace actual human morals, and assume that because the market is "free" or essentially some uncontrollable algorithm, anything it does is moral by human standards. It's easy to throw your hands up and say "oh, well that's just what the market will bear" and assume all moral responsibility has been accounted for. But I disagree.