Most of my customers depend on the email notifications when leads come to their website, and those emails contain an unsubscribe link at the bottom. 

Often I configure the form emails using the form's {{ Name }} and {{ Email }} content as the ReplyTo settings, so that clients can easily reply to the message and contact their new customer.

However, that customer gets the unsubscribe link too.

Sometimes, someone gets confused and clicks that link, which then shuts down all future lead emails notifications from their website.

Disaster...  Until I am made aware and can go re-establish their notifications.