If they activated the paywall for Googlebot, they'd get no visitors from Google searches.
If they deactivated the paywall for Googlebot, but activated it for visitors, they'd get banned from Google for expertsexchange behavior.
They must figure that random Google visitors are worth more than the people who are clever enough to Google the article titles they want to read to work past the paywall.
Comments
If they activated the paywall for Googlebot, they'd get no visitors from Google searches.
If they deactivated the paywall for Googlebot, but activated it for visitors, they'd get banned from Google for expertsexchange behavior.
They must figure that random Google visitors are worth more than the people who are clever enough to Google the article titles they want to read to work past the paywall.