Not sure why you’re getting down voted because you’re right. There is no magic to Hey, you explicitly tell it which “folder” a sender’s email should go to. It’s not perfect because some senders use the same address for different types of emails (receipts versus offers), but there’s no magic about where an email from them will go.

Hey's biggest fail is missing notifications for first time senders. It seems to assume people are constantly using email. But for me days can sometimes go by until I am active rather than reactive on a particular account. With Hey, I only then realized that there were two emails stuck waiting for me screening them.

This is why I'm cancelling my hey subscription as well. I get that they are upfront about it being a feature, and it sounds great at first, but it's made me paranoid about missing mails now - a feeling I never got with any other service provider. It's a shame, as I got in pretty early and bagged a great account name (firstname @ hey.com). But it's not worth sacrificing my sanity for vanity.