Market segmentation makes sense in principle. If Joes Bait & Tackle shop wants to use your font, it makes sense that Joe should pay less than Google. Unfortunately, for an intangible digital thing like a web font, coming up with a payment scheme leads to all kinds of absurdities.
That said, I think once you get to pre-paid expiring page views, that's a sign that we've entered the realm of insanity.
They'll be happy to let use the fonts for whatever you want but you'll have to pay more.