I turn off data when traveling international. I was recently in Canada and could text free (included), but data was pricey, so shut it off when not needed.
I also go to France often enough that I bought an Orange France Domino for wifi and run all my data through that, but can still get calls on my US phone number. I just shut off cellular data and avoid VZW int'l data charges everywhere in France. 🙂
I'm still on iOS 6. So, am I to understand it's not possible to shut off cellular data on iOS 7?!