For the Symbolism of it!
Being hip and trendy seems to be the in thing these days. You want to fit in and be apart of something. Pressure surrounds you no matter your age, economic level or geographical location.
Being cool use to be what kind of car you drove, what style hand bag you carried around, today, just about anything that is in the know is cool. Until every body is doing it or wearing it then you look for something else to symbolize being different with.
Could setting a New Years resolution be considered hip? Sure it could. All your friends are setting them. You could just fly underneath the radar screen, (just incase you fail this time) while everyone else is on the band wagon you can fit right in. Get excited with them. Well maybe a false sense of excitement. What do you really feel like when you do something just because someone else is doing it or if you just want to please them? Not very fore filling to you, is it?
The holidays bring with them family, emotions and yes pounds. Once all the excitement is gone, what are left are leftovers; food, excess weight and a sense of let down. You need something to pick you back up after the crash. Kind of like a need for sleep after the Thanksgiving meal. So maybe you set a New Years Resolution