I completely understand that bulk confirmation mails are a no from a spam perspective. But it creates a problem when mailpoet is added to an already active site.
New members get welcome mail, but there is no such option to send to old members. Sending confirmation mail to old users (700+) is tedious. Yes, a pop-up subscription helps, but there should be a way to communicate to already old subscribers that a new mail service for newsletter is on offer. They can then decide to opt in or not.
It may be an onetime possibility. It can even be a fixed text notice, that ensures that no spammy stuff is included. But I have been scratching head to send mail to my 700+ wordpress subscribers to tell them that monthly and weekly newsletters are now available for society members.