Once this app becomes large enough to get on Google's radar it'll likely be shut down.
The makers of spam tools often make lots of money in the beginning (e.g., XRumer blog spam), but once they get big, adjustments are made (e.g., CAPTCHA for blog spam) and the tools become ineffective/useless.
That doesn't make it not spam. Spam provides an overall negative value to my life, even if an individual message could conceivably be useful.
Which make it even more ironical.
Let's put that good ol' spam filter to the test! I even operate under Inbox Zero, so rest assured I'll deal with every email the supposed mob is going to send me.
If it's an HOA or small mailing list (obviously without DOI), then what is your click tracking functionality for? (I mean, the question answers itself...)
I have no doubt Google will discover this and block the service, and we'll all be better off for it.