I have helped a friend who does small, static marketing sites. In addition to needing a server for only thing (forwarding contact forms), I've noticed that mail from the low-end shared hosting her clients generally choose is extremely unreliable. So I've wondered if there was a need a service exactly like this. However it seemed so basic I thought... nah.
It is for me. I do mostly static sites for small business, and use embedded forms from jotform.com but would really prefer to be able simply to post the info to an external server which handles sending the email.