IN-APP Purchase Question ?

Hello, quick question, I hope I explain myself correctly.

Topic: In-App Purchases.

Example: Instagram like App/social media network. Post content for others to view for free. But, approved affiliate users can post premium content for sale to other users through an in-app purchase.... these affiliate approved users would be getting commision for sales of their content.

Is this doable, and by doable, I mean withen the App Store Guidelines and/or policies. I've tried finding info on this.... and I'm now turning to forums for help

Does anyone know of any examples of this currently being used in Apps?

Thanks,
Eric