Your e-Commerce store site usually gets all kinds of visitors on daily basis. The online traffic includes new customers, returning customers and online users who are simply browsing your website. Out of all visitors, some online shoppers make a purchase and some don't but there is a completely separate segment of online visitors who sign up for your email list. This segment of visitors are usually interested in learning more about your store, what products / discounts you have to offer and how signing up your email list can benefit them.