For the record, I agree.
However, playing Devil's advocate for a moment, I'd say that comparing game laws to movie laws doesn't make a whole lot of sense. After all, games by definition contain a strong interactive element. It could easily be argued that watching a violent act being carried out on TV is something very different from playing a simulation of acting out that violent act yourself. In that light, it's not so strange that people think it's more important to keep small children from playing violent games than it is to keep them from listening to abusive lyrics or watching violent movies.
Also, this isn't such a straight-cut freedom of speech case as you make it out to be. They aren't trying to ban those games entirely. They aren't restricting anyone's speech, they simply want to keep potentially harmful products out of the hands of children. While it could (and should) be argued that this is the parents' job and not the government's, this has nothing to do with being free to express yourself. Whether violent games are harmful to children or not is another matter, but if you believe that they are (and the people pushing this law obviously do), then wouldn't it be a good thing to prevent children from getting their hands on them? There are laws against underage drinking as well, and I don't see anyone protesting that (at least, anyone sane).