I think Omni had one but it was only used once. Maybe it was even just set on a single member. Invisionfree also had it. Typically people just ban if they have to restrict members. The current setup is more as a compromise to the fact the current board rules might restrict people's free speech (although technically they can still post what they want, it's just that there can be consequences for some stuff). Some users might just be unable to do much effort to restrain themselves from being rude , for example, but might still be willing to continue posting positive contributions, so that's where that feature comes into play.
In general, CodeWalrus is stricter toward provocative remarks and the bar at which something is considered intolerance is lower. For example, if an user over here tried to restrict somebody from talking about moe girls in particular or bash him for doing so or restrict reddit screenshots posting that are SFW it would be considered intolerance (as in closed-mindedness towards specific hobbies) under our policies and be a bannable offense if done repeatedly. Of course it depends if people are flooding/spamming, though (for example if someone posts image macro or Youtube links every 10 second for long periods of time). The 1st site rule about rules/lack thereof applying to everyone is to prevent, for example, some religious extremist from whining about someone using the word Christmas or people from thinking that just because someone is a long-time and expert community figure then he is entitled to break the rules as he sees fit without consequences.