[reaperducer]

They're not meant to be shared in social news websites.

From your link:

"Where is it appropriate to post a subscriber link?

Almost anywhere. Private mail, messages to project mailing lists, and blog entries are all appropriate. As long as people do not use subscriber links as a way to defeat our attempts to gain subscribers, we are happy to see them shared."

[debugnik]

Having access to nearly every paid LWN article on a news aggregator certainly feels like "a way to defeat our attempts to gain subscribers". But others said these links are subscriber-specific so I guess LWN is fine with it if they aren't taking the links down.