What's the implication here for sites wishing to monetize by selling (hashed) email lists of their users? Take Reddit for example, it could make a lot of money

What's the implication here for sites wishing to monetize by selling (hashed) email lists of their users? Take Reddit for example, it could make a lot of money by selling the (hashed) list of users subscribed to /r/travel (or almost any other sub). Suddenly all those users with adblock who won't fork out for subscriptions would be generating income. I know most TOS's say they don't share email addresses, but sites could theoretically specify that a hash of an email address be allowed.