Ask HN: Are Paywalls allowed to show Google crawler full content but not users?

Today I noticed the Washington Post I'd quite naughty.

Even when you click through from a Google search, they still gate the article content behind a paywall. Clearly they fed the full article to Google bot and Google news, but then show a different page, sans article content, to web users.

Is this a violation of Google search policy? If yes, does Google even care enough to enforce it?

I think this sort of publisher behavior makes for a hostile and overall very poor user experience.

.. Especially when Wapo is already bankrolled by greedy Uncle Jeff. But I digress.