Why do people not sign up for Mandrill / Postmark / Sendgrid etc when creating an app like this so the confirmation email is delivered instantly and not placed in your junk folder?

App looks good, was thinking about creating something like this for my own use. My use case would be for monitoring a forum 'Whats New' page so we can be alerted if a thread is started about our business. But we would need the alert much more frequently (every hour at least), and wouldn't want the same alert over and over again.