An ability of directly communicating with your users has a very positive effect on a valuation of the company. One thing is when you have N million User IDs, and another - N millions emails.
Also if you are running a service with termed licensing, an email communication is how you drive the license renewal process. This sort of communication does not qualify as spam, because it is more of a service reminder rather than an unsolicited commercial offering.
Also if you are running a service with termed licensing, an email communication is how you drive the license renewal process. This sort of communication does not qualify as spam, because it is more of a service reminder rather than an unsolicited commercial offering.