Rant: Email Newsletters

I use Campaign Monitor to send my (almost) monthly newsletter, which informs my subscribers of my new photo galleries and forthcoming The Travel Photographer's Photo~Expeditions™. Although these newsletters are only sent to those who subscribe through my sign-in box on this blog, I still get a spam notice, or even two, once in a while.

So here's the rant:

1. The mailing list for my newsletter is by subscription only. In other words, the person wanting to subscribe has to fill in his/her email address and his/her name in the sign-in box.

2. Upon doing so, each subscriber gets an auto-rely from me thanking them for subscribing, and saying that they can unsubscribe at any time by clicking a clearly marked link on the newsletters.

3. So why report my newsletter as spam? Even though I have a minuscule spam rate, it's annoying. Sending a newsletter costs me money, and if subscribers change their minds, the unsubscribe option is there! So use it, for heaven's sake!

The definition of spam from Wikipedia is this: "Spam is the abuse of electronic messaging systems to send unsolicited bulk messages indiscriminately."

Obviously, my newsletters are neither unsolicited or indiscriminate.

So is it illiteracy? Confusion? I'm mystified.