I'm an Italian-American originally from southern New Jersey and can indeed confirm their existence, although I am not among their ranks.
They're most common in the northern half of the state and in the summer can be spotted anywhere up the jersey shore, although they are most likely to be seen at points north of Barnegat. During these summer months, though, Seaside Heights (better known as Sleazeside) contains the highest concentration as they trickle down from their parents houses in the border counties and Long Island. I would suggest staying out of Seaside as they have been known to get a little aggressive, especially after a night of hard drinking. Alternatively, sporting a tight undershirt and a blowout haircut may facilitate assimilation, although its temporary status cannot be guaranteed.
Seriously, though, yeah they exist. Most are high school and college age, and some never outgrow it unless they leave the area. I went to college in the middle of Virginia and we had a few, but unlike back home, they totally weren't appreciated (or even understood) so most toned it down quite a bit. It was really funny during my freshman year when people would just ask them "What the hell?" and they were totally caught off guard by the notion that their appearance wasn't anything better than comical there.