usually whenever I hear an alarm go off, I go running outside (sometimes with some sort of weapon - usually my bokken/bokuto*) to attend to it. Or if it's too far away and I can't tell exactly where's it's coming from I'll call the police and tell them that there's an alarm going off near my vicinity.

Alarms don't work if people don't attend to them.

At the last two places where I lived (which was much more urban - I now live in suburbia) there were often alarms going off, especially from this one house across the road... and so many times I'd wake up in the middle of the night, rapidly try to throw some clothes on, grab my weapon, a torch and my mobile (I had the local police number on speed dial) and run out in thongs... gah.

...having said all that I personally don't rely on alarms as I find that other than freaks like me, most people just ignore them. They shouldn't (after all, if it was your alarm you'd want people to attend to it) but they do.

My last car had an engine immobiliser instead of an alarm. My house is already immobile.

*any kind of sports bat would also do quite nicely - cricket bat, baseball bat etc.