I don’t understand this argument at all.

You mean to say you signed up for a service or subscribed to a newsletter, then see an email from the service or newsletter and don’t know if it’s really that company/person?

Did you check the “to”? Do you look at the url of the unsubscribe link? (Harder when click tracking is on, I know)

And you would rather hurt that company or person because you don’t feel like taking the time?

This makes no sense to me, and I hope I’m not in the minority here.

I think he means that a lot of pure-spam emails include an unsubscribe link that actually proves to the spammer that they've reached a live person, and then they'll resell your address to everyone.

It can be difficult to tell if it's a fake UniversalBankCo email or a real one, even if you are a UniversalBankCo customer.