I think we can agree that its complex. I'm not arguing for or against IP. And I agree that the threshold is a fuzzy one. Companies demanding that they take down a home video of a kid dancing, merely because a song they produced is playing in the background illustrates how fuzzy that is.
(To address your building issue though - the architect certainly did have a large amount of creative control when designing the building. But he was commissioned by a company that funded the construction of the building. The architects did their job, were compensated for it, and has no more say. The company that owns the building may try to restrict the _act_ of photography, but they can't very well say "You're not allowed to record photons that bounced off our building - those records belong to us."
But thats besides the point - I wasn't arguing about who has control over a photograph. I was objecting to the idea that there was no creative input into the taking of the photograph. )
But I think the same thing applies to peopl in a crowd. If the people in the crowd had any legal rights over any image they appear in, then security cameras, images of sporting events, of concerts, and of general life, would all be sued into oblivion.
Laws aside, I believe that if someone doesn't want to be photographed, then you shouldn't out of respect, especially if they have a reasonable expectation of privacy. But if someones in a public place, the photog is not bound to get permission from each and every person who crosses his viewfinder. Ethically, if the photog expects to make money or widely distribute the photo, then maybe an attempt should be made to gain consent before, or after the photo, if possible. But IMHO that's more of a gentleman's agreement than anything that should be morally or legally required.