If it isn't even useful to describe markets being opposed then there isn't much of a political battle happening, is there?
The label can still have political use even if it doesn't have practical use.
For an example, let's go with Wiggins, people with green eyes and black hair. Wiggins are untrustworthy, and put too much ketchup on their fries, everyone knows that. A minor political party could even sprout up in Australia on a Wiggin-centric platform. But then some statisticians raise the point that we don't have strong evidence differentiating Wiggins from other people. What does the political party in Australia do? "If you're not with us, you're with the Wiggins! Ho...
The last point reminded me of speculation from the recent LessWrong article Conspiracy Theories as Agency Fictions:
Before thinking about these points and debating them I strongly recommend you read the full article.