¿ How to opt in ebay buyers ?

Hi,

I have been selling on Ebay for 6 months, i have a seller account. Even tough my sales are really good, i can't run email campaigns because no one subscribes..

On the other hand i when i buy something on ebay, i get an auto-responder email from the seller immediately without subscribing. Also when he runs an email campaign (such as mailchimp) it arrives on my inbox; not on my spam folder..

How do they do it? How can they get me as a subscriber?

I know when somebody buy something i can see their email information; but as far as i know it is not ethical to run email campaigns without having them as a subscriber. I would like to implement the same system for my store. Any idea?

Thanks

They probably take the time and manually do it anyway

Scrap the emails from paypal or your sell notification and make up a list!
Or do it manual like Cushy Prisons said