Molotovs was the response to Yanukovich crackdown on Nov 30, beatings of journalists and non-journalists alike, and attempts to limit individual's rights (Jan 16 laws) Cause and effect - there's a scene in the 2nd Matrix movie about that
You make it sound like its ok to throw molotovs at people who do their job and follow the law and who are not personally in any way harming anyone. There are tons of videos of nazi-like protesters throwing molotovs at police officers who are doing nothing except standing in front of government buildings.
The protesters were the first ones to go outside the boundaries of laws - by staging continuous protests in the public square, erecting tents and barricades and disrupting the normal life for the rest of the citizens. The police tolerated them for a while and then decided to do what they are obliged by the law - to stop the illegal activities. And since then the situation seems to have escalated with protesters using molotovs and live ammo.