Jetpack Subscriptions – What if I only want to collect the subscribers' email?

I’d like to use this plugin only to collect subscribers’ email address, for external newsletters, etc, NOT for blog posts. I have customized the button like I want it and all, and realized too late that the subscription is connected to new blog posts. Does anyone know if it is possible to turn off the automatic notification to the subscribers and customize the plugin for my collecting purpose?

Thank you so much in advance!!