1) The guy in Buffalo will not be let go because the defense lawyer abandoned that client. Cut/paste repo's earlier comment.
2) If the question of commenting on a previous post is in reference to the Sharia Law taking over the American Constitution in Dearborne, that video really proves nothing. The end all be all of legal/not legal in this country is the supreme court, not a bunch of beat cops. It is likely that their arrest and detainment would be found illegal if brought to that level, but that wouldn't help the filmmakers' point.
Unfortunately, they are provocateurs. This is simply a video generated to get people riled up. On the other hand, there are limits on free speech. Inciting riots is one. Riding the fine line between arousing base emotions like fear and anger amongst people and inciting riots is a difficult one, and the police are probably taking the conservative route and being proactive about the situation. If the reverse situation were true, and Muslims were standing outside passing literature near a "Celebrate Jesus Carnival", the police would certainly have a similar response.
As soon as the supreme court rules in favor of Sharia Law, I may be convinced. Otherwise, it's just political rhetoric.