Arrrgh those damn kids! 
"Oh, I like freedom.
I just only want it for people who don't do things I hate.
Like stand in front of a building."
More like loitering, beating people up, getting drunk and making trouble, throwing things at passerbys, destroying public property...things like that.
Because everybody under 25 has no decency, culture or respect....
Seriously, do you even think before you post?
Yes, why you ask? Such a strange thing to do for you?
This thing has a limited range. It's used to disperse troublemakers in a small area. Somehow, people are thinking that young people world-wide will cover when one of these things go off. There are other methods of getting people that bother you off your property, but I'd say they are usually more personal and require direct contact. And I bet it's cheaper than hireing a bouncer.
Not exactly sure this is the best way to go about it, but it beats doing nothing.
This device, like any device before it, can be abused.
And indeed, if it is the owner should be punished. By why always assume the worst?
If you intend to annoy people, the laws involved don't even need to be about noise, since you are purposedly disturbing people.
If a bunch of pricks come into a store, loiter, harass the clientele and refuse to leave, who is harrasing whom?
Yeah, you can call the police, but they have better things to do.
Didn't they invent some sort of precise headache gun a while ago? Wouldn't that be a better than something that has an area effect?