It's far from perfect but it's infinitely better than on the mainland.
Nothing justifies "resorting to violence" in HK today. The violent actions along with anti-Chinese displays are in fact counterproductive because they push the central government to tighten the screw and unite the mainland's public opinion against them.
Many of these protesters have no democratic culture themselves. Anyone who disagrees with them is wrong and an enemy that must be fought by any means.
If they're basically going to be steamrolled by a rather unsubtle up-and-coming superpower, perhaps they have no choice. In fact IF violence is all you're left with (and that does seem to be the case as legal recourse is blocked) then violence is necessary.
The CCP is not backing down until it has borged HK.