So lets be honest, skiing park is way more fun than gate banging. but if you want to see why people race, look at Jon Olsson. He went from being a grade A pro park skier who gave us our first double flip, JOSS, and JOI. Now all he is is a B-A grade GS racer who spends most of his time in the Europa Cup and occasionally gets a WC start, yet he makes way more money. Racing is where the money is at.
Even though i find park skiing to be the more fun expression of the sport there is something to be said for racing and the foundation that training for it lays. believe it or not most pro park skiers and almost all big mountain pros got their start as racers. Shane raced for CU in college, Hoji was a racer in canada, and TJ Schiller was a mogul skier, just to name a few. Most of them wanted to make it in a competitive part of our sport but didn't have the size or the patience to to make it happen.
This is what lead to the creation of free skiing, taking a foundation of racing and good skiing fundamentals and adding a component of personal expression. so no matter what you do, race, park or big mountain, don't hate! go out and try to make yourself good at every part of skiing and you might see it help you improve your skills in the park or on the race course.