I agree everyone has a right to state their opinion. However, if said opinion is something along the lines of "I want to rape your mother", I will probably beat you to death. Some opinions can be debated and just not sound right. Some people just have no mental blocks, are pretty dumb to general respect and tact, or are undiagnosed sociopaths. I've been unfortunate in having to deal with the public, and have noticed that 1 out of 10 people just are completely frightening in some hidden yet obvious way, or just they are for lack of better words talking wad's of psychotic meat.
Some people dont have the knowledge that some opinions, at any time, may not be an appropriate thing to say. Serj Tankin of System of a Down can have the opinion that 9/11 happened because of our presence in the middle east, but you dont say that the week after and the buildings were still smoldering. You don't tell one of your friends after he had a fight with his girlfriend that she came on you, and act like you did him a favor turning her away. Just some things in like, are not followed with words, sometimes its impacts fith fist, feet, and various found objects.