If a critical mass of the dominant free providers were to do this, would it deter consumers from using ad blocking or merely piss them off and lead them to go elsewhere? From Boing Boing:
The company says it’s not policy to do this — yet — but they’re testing locking Yahoo Mail users out of their accounts unless they turn off ad-blocking.
Many (many, many!) Yahoo Mail users actually paid for their Yahoo Mail accounts, in the form of a bundle with their cable or DSL subscriptions. Presumably you can get around this by just using a mail-client to pull your Yahoo Mail over POP or IMAP (the last time I checked, you could use Gmail to read your Yahoo Mail this way).
http://boingboing.net/2015/11/20/yahoo-blocks-some-users-from-a.html
