Is it because they won't break the law, or because their husbands/fathers won't let them? How many of those women would gladly give up those restrictive clothes if they weren't afraid of being murdered? That's what it comes down to, you know. They are taught from early childhood that they are property, Muslim women who must always obey their fathers, their brothers, their husbands. And the penalty for disobedience is death.
Aside from that, laws based on protecting the public must always be given preference over laws based on superstition and wishful thinking.