David Pogue:

Look: international roaming has always been insanely priced. And like many people, I’ve always assumed that there’s some reason for it. International tariffs, maybe. Special equipment. Something. It couldn’t be as simple as outrageous, consumer-hostile greed, could it?

Yes, it could.

This is a very clever thing for T-Mobile to try — even if the data will be hampered by very slow speeds. As with SMS, the carriers have long used roaming charges to gouge customers simply because they could.

The general rule seems to be that being a dick is not a sustainable business model.