CHINA is allowing the people of Hong Kong to exercise democracy. If they have democracy then they have the right to protest. In a democracy, it is your right to support whom you want to support. We too live in a democracy and, hopefully, we should support people who also want democracy.
Yes, business and security will be affected. But just to remind everyone, do you think the French and Russian Revolutions could have happened if people kept quiet and worried only about business and security? What about the American Civil War and the civil rights protests of African-Americans led by Martin Luther King Jr? What about the Iran Revolution and the Arab Spring?