Is there something I'm missing?

I just got my new IPOD Touch, and downloaded the new Zagat Guide app. Perfect, except that it requires WiFi access to use it.

But, the whole point of this kind of Guide is to use it "on the fly" when you're standing on some streetcorner wondering where to eat. I don't have WiFi access on every corner. I thought the content would be downloaded to the IPOD, but apparently only the operating software is actually present, you need to go online to search for anything.

Is there something basic I'm missing? Do most apps require WiFi access??