So I'm The Dick?

I've got a question for you all. It's kind of an existential question about dicks, and if I am one. I'd appreciate your input.

Today, I got an email from a guy I don't really know. We were both on a mailing list in the early / mid 2000's for a website that posted links to satire news stories. He was announcing his new project. I won't mention who or what the project was, because I'm not trying to call the wrong kind of attention to anyone.

His email was addressed to 25 people, all of who were listed in the TO: field -- he didn't put them in the BCC field, which I believe etiquette dictates should be done, because he just exposed my email address to the list of people he was communicating with. His message read:
I'm just sending one (and only one) email to let people know that [the new project] is done. It started out as audio only, and I still am going to release it as a podcast, but I thought it would work well in this format as well. Please take a gander and share it with your friends on Facebook and Twitter if you like it. Have a great day! [ Link to project ]

I replied:

You're welcome for me not berating the absolute shit out of you for not only spamming, but also not putting everyone's email in a BCC. It's your fail they are getting this reply-all. Have a great day yourself!

 Within minutes, I got a few emails from 3 people saying I was a dick, and that I overreacted. I also got emails from 2 people saying his faux pas pissed them off as well. A good friend of mine called me on it, and said I was too harsh; that he was working his connections and that I shouldn't have shamed him in public.

My feelings:

He wasn't a "connection" -- I didn't know the guy at all, it just so happened I was on a list back in the day he was on. I feel he wasn't trying to share a link with a friend, he was trying to get someone with a voice to share his project. He wasn't concerned with my thoughts, he wanted shares on Facebook and Twitter. But that wouldn't have been so bad if that's all it was. But he put my email address in the TO field along with everyone else's, exposing my email address. It pissed me off, and I reacted.

The question: did I overreact?  Was I the dick? Or did he deserve a shaming?