Exactly and to bring it back to buildings, for e.g., you are free to photograph every McDonalds restaurant exterior you wish. But you can't sell a coffee table book called "My Tour Across America Documenting McDonalds' Restaurants". The logo and brand name are trademarked and therefore you would need consent from McDonalds. I think it gets more complex when logo's and/or trademarks become centerstage as opposed to say a cityscape with a golden arch way in the background and the intent if the book is to document skylines or something benign.