I suspect the free tier falls (at least in some sense) under "marketing" rather than being expected to return a direct profit. It's enough to be useful, but (I

I suspect the free tier falls (at least in some sense) under "marketing" rather than being expected to return a direct profit. It's enough to be useful, but (I assume) little enough that enough people subscribe. For comparison, my account has roughly 3.5M queries over the past 30 days, and 298k of those are to a single domain :P.