Why do people kiss after the countdown on new years?

i was just checking out videos on the net of new years eve 2009/2010 in times square. i just reserved me a room in n.y.c. for new years and i'm gonna be heading to time square for the first time for new years... anyway, and i'm seeing all this crazy action going on like, the fireworks, confetti, the people, the lights whatever, and then you see a whole bunch of people just locking their faces together just at the same moment everyone yells, "HAPPY NEW YEAR!" and i'm like,,,, whhhha? and they keep going like, they're in their living room with family or something. i'm thinking, man these people are like from, Timbuktu and you go there for all that energy and all you do is kiss? looking like you're making sure that you miss everything that's going on around you. who ever thought of that? like at 12am we all gotta kiss???? i'm telling you, if my girlfriend does that to me when we're over there, ima kick her in the nuts and she's paying me back my whole trip... but i think she knows better.