The food truck phenomenon has been raging for a few years. The outlaw fringe element seems to excite the imagination. In some parts of the city, food truck roundups bring communities together. Bal Harbour, Surfside, and North Miami Beach have embraced the idea by hosting parties at Haulover Park every Tuesday from 5 to 9:30 p.m. at the kite-flying area at 10800 Collins Ave. There's a DJ, plenty of dancing, volleyball nets, and huge blow-up slides. It's BYOB because there are no liquor vendors.