Yet when those hippie punks burn a flag, aren't they begging for our freedoms to be outlawed? "...and to the Republic, for which it stands..." The flag is representative of our nation, our laws, our freedoms. When one chooses to destroy the flag, he is essentially saying "Turn my freedom to ash." A flag isn't just a thing, really, no more than a crucifix is just a thing. They are something more because they represent something much larger.
Suppose they are. It's no more permissible to restrict their right their right to do so than if they said it or wrote it. Such stupidity is best countered in the marketplace of ideas.