The ones I'm thinking of (eg. NYTimes, WaPo, WSJ, etc) are all username/password.

What kind of paywall are you thinking of?

How do you think this add on was working? do you think it was brute forcing the password of all the sites you were thinking of?

I'm less concerned with the implementation than I am with the principle.

In principle, I have reservations about exposing content to search engines but then requiring payment to read it. Especially if it's non-trivial to filter out the sources that require payment.

But a plugin which works around an attempt to restrict visibility of content to those who've paid for it ... I thnk the intent here is wrong.

I think it's ok to have information that's only accessible to a restricted set of viewers.

It's not that it's not possible. It's not that the implementations aren't dumb. It's that the principle of "if I want it, and I can do it, then it's ok" doesn't really hold up, IMO.

They just bypass the paywalls by pretending they are google, there's no username or password involved.