Actually it would help you here. In this case your real address isn't exposed unless someone guessed the exact version you used to sign up.

What do you mean? If [email protected] is in the leaked list you know that that [email protected] is the "real" user and also is someone who has BTC.

There was no leak. The API allowed you to see whether a given email had an account associated, so someone churned through a big list of known email addresses to find accounts.

If you do a filter like this: All mail that arrives to [email protected] is important. Everything else is spam. Of course you might not get emails from people who sends emails to [email protected] nor [email protected] because the emails go to spam.