My take
What I understand as totally reasonable use of an iPad camera:
Taking pics of anything within 2-3 feet of you, tops.
Using it for documents (maybe with an OCR program).
On-site inspection pics for construction/art/whatever.
FaceTime.
What I DON'T get:
Holding them up at events.
Taking pictures of anything that should require a zoom lens.
Basically, everything that people also use other point and shoot cameras when they shouldn't (low-light concerts, anything far away that's not supposed to be a landscape shot).
Recording audio and video from the audience (your kid's recital will sound horrific, and we all know you're never going to watch them again yes, we have plenty of VHS tapes sitting in cabinets with this very thing on them).
For most of the stuff I don't get, you're likely blocking the view of others to get a really ****** quality pic.
For all the other stuff, it makes sense.