I’ve unsubscribed from many newsletters just because I wanted to change the email address but that option wasn’t available and I’m not about to have to go hunting down how to sign back up again. I have a strategic email strategy where I don’t use ‘real’ email addresses for newsletters I subscribe to (I’m writing a post about it).
I see it the most with Infusionsoft emails but there IS an Update/Unsubscribe option.
Also make sure to include at least ONE link back to your primary website. Don’t make it hard for people to stay connected with you!