[dubcanada]

You do know that email clients send an email to the email sender that gets recorded correct? For example if you press Mark as Spam in hotmail. And AOL sent you the email using MailChimp, you will show up as "spam" in MailChimp.

That also gets dinged against the sender and an account can be suspended if its too high.

TLDR; you're not using it as it was intended.

[rvkennedy]

It improves their behaviour. I have lost count of the number of mailing lists I have had to unsubscribe because I simply used their product, without explicitly asking to be put on the list. That's spam, whether they bought my email, or just took it from some other list that they legitimately had.

MailChimp etc are for messages you explicitly sign up for.