I'm sure this is taken out of context.

However when I open iTunes to actually purchase an application, accessing the section for buying applications is very clearly done through the label "iTunes Store", and the status bar even shows "Accessing iTunes Store" as it goes to retrieve the list of applications. The emails I receive that contain invoice information also come from the "iTunes Store", so it would seem to me that at least if you buy them through desktop iTunes, and not directly on the device, you are bound by the iTunes Store terms of use and cannot use them for commercial purposes. For apps bought on the device it seems to only display "App Store", although I do notice emails that contain invoices still seem to come from "iTunes Store". So I would say it is highly ambiguous in that case, but based on this I would definitely buy these apps "on the device" rather than through iTunes.