Face Off Street Photography

I'm honestly just curious. Because where I'm from (Germany) you aren't allowed to take pictures of people "in focus" meaning - if they are in the background and not the "topic" of the picture, its fine. If you take their picture as "the topic" their right to their own image outrules the Freedom of Speech, as you should have control over where your picture is posted - if you're the main focus of said picture. In your cases, the people are definitely the focus and therefor you would need their explicit permission to post them anywhere. If you don't you can get in legal trouble.