Yesterday was a fricken snow storm and Brockton is hardly mayberry, I am neither surprised (or upset) that they wouldn't send a cruiser out looking for a car that "might" be there... They were busy with other things... Quite honestly let him/his friends go on the wild goose chase of where his car "might be", calling the PD seems like a waste of resources to me...
That said, if it is/was just sitting on some street some place it has probably been towed by now anyway. Virtually everyplace has some sort of "parking ban" right now and cars left on the side of road get towed pretty quick when they plows are out...
If your friend reports the car STOLEN, when it turns up (in Boston, Brockton, Wakefield, whereever) that PD will recover it and let him know.