Well,when I say right down the street I mean maybe a 20 minute drive (in light traffic).However,all the towns I mentioned are considered suburbs of NYC (the "Tri-State" area) and,as a result,*every* house you see in Greenwich has some sort of "Protected By ADT" sign in front.
Alarm systems are a decent deterrent for break ins and robbery on an individual basis, but it’s not going to do much good in the face of anything of a larger scale.