the reason to oppose these laws is that they don't work. rather, they provide fresh fuel for stale hate propaganda. if you shut down the nazi newspaper, don't be surprised when they use it as evidence to prove that the jews control the media - and when people are dumb enough to believe it.
further, when you attach consequences to opinions, what you do is just drive them underground. people learn what they can say in public and can't, but they don't actually change what they think. this fuels the resentment. it leads to groups of people yelling "i can't say what i want because of THEM". one would have to expect a long term policy of this sort to eventually lead to a violent backlash, as it isn't eliminating the hate but bottling it up for eventual explosive release.
there are various approaches to dealing with racism, but they generally have to do with working it out through integration and dialogue, not threatening people to shut up or else.
that doesn't mean i think hate speech should be without consequence, but i think it should be treated as a tort and come with some very heavy burden on the person launching the suit. it's ultimately a type of defamation when you work it out; if i say something disparaging about all people of a certain characteristic, the crux of the problem is ultimately that it simply isn't true. yet, the law doesn't challenge just any false statement, it challenges false statements that are shown to cause harm. if somebody's racist tirade has a demonstrable consequence, the person that wrote it should be held responsible for it and forced to make the situation whole.
otherwise, they're just a moron running their mouth off and should be treated as such - which generally means just ignoring them.