The Ministry of Statistics thanks you for your contribution. We have noted your click through rate and have added it to our population sample.

You're getting downvotes for the unconstructive snark, but I feel there is a salient point in there.

Unsolicited email = spam; simple as that. And by that association, anything and everything being sold by those emails is suspect. After all, if you had a product or service that people actually wanted to use, why would you resort to spamming?