Why WordPress Product Owners Need to Capture User Email from Day 1

Anyone who has ever built a product for WordPress (plugin or theme) and tried distributing it via the WordPress.org repository knows that user emails are not part of the bargain. You do not have access to this direct way of communicating with the people who are trying out and using your product. As a product owner, you desperately need to be able to contact your product users and there’s a great way of doing that, only for some reason, it is not the “mainstream approach” in the WordPress ecosystem.
No Access to User email
That holds true for marketplaces such as CodeCanyon, ThemeForest and others, where they do not share client email addresses with their authors. The reason for not sharing client email with sellers are quite obvious. They simply want to lock you in, and do not want you to engage in any communication via a private channel (email), over which they have no control and through which they cannot charge their commissions ($$$).
With the official WordPress.org repository, the reason is simply related to an attempt to maintain the user’s privacy and to protect their inboxes from getting bombarded by spammers.
While the reasons may be different, the end
Source: https://managewp.org/articles/13792/why-wordpress-product-owners-need-to-capture-user-email-from-day-1

source https://williechiu40.wordpress.com/2016/11/08/why-wordpress-product-owners-need-to-capture-user-email-from-day-1/