I asked this question in the Wolfram Blog; I got a reply there:

You will not need to purchase the in-app purchase to pan or zoom 3D objects. EnterpriseCDF documents also require no in-app purchase to make work. As for having an iPad demo the app, we’re certainly hopeful!

I'm hoping teachers understand: it would be tremendous for a student to create a CDF and then be able to see it run on an iPad. It ignites imaginations to write the code and then see it come to life. The CDF player is one man's (and his company's) vision for visualization. Authoring the code in the Wolfram Cloud or on some PC (including Raspberry Pi) is a tad convoluted, but kids should pick up that fire drill quickly. It's all just part of the game.

I'll have conversations in my circles to ask about getting this app in the Apple Retail Store's demo load. This should not be too hard; it is a Win-Win for both companies to have world-class software running on these sales floor machines. A pie-in-the-sky idea would be for store's Creatives to have presentations walking kids through the steps to author and deploy CDFs. We cold make this happen!

I'm guessing this has to do with the fact that CDF files could contain bad words and/or 3D renderings of "crude humor". Clever CDF coders could computationally generate the mildly profane output. In other words, statically filtering out all potential objectionable content in a computational environment is problematic.

Not sure, but the network functions are pretty edgy (hey, you asked...)