"[T]hey want a good salary but they prefer work life balance over working 60 hours a week and making it to the very top."
I'm in the fall season of life and agree 100% about finding the right work/life balance.
But, I also believe life - especially early in the "adulting" portion of life - is also about not burning career options. One way of not burning those options is showing the "boss" you are the hardest worker he's ever seen - arriving early, leaving late, producing quality work, communicating clearly in writing and orally. Hard, efficient workers get promoted - as you climb the ladder you can take your foot off the gas.
A person can always find a less imtense job, but once in that better balanced job, you have real trouble moving back up the chain. (Money in a vacuum is meaningless; but it is a lubricant for life.) Both mom and dad started in a "big grind" career; it allowed us to accumulate enough to begin a business where we controlled our time and owned our lives. We want out kids to own their own lives - the earlier the better and figured that Princeton would at least give them that option.
In many ways, those first years in a big law firm or at an IB outfit is a crucible. The long grueling hours really last only through the first 2 - 5 years; and those hours weed out many (D views it as getting a Masters and it requires that intense effort over that period of time.) Subsequent prospective employers also pay up for that "training" period.
Comparing S to D, S's first job experience (milb) gave him time to figure out he did not want a 70+ hr job. So he "sacrificed" salary for time; when he travels on business he works 4 days a week (generally staying an extra day to play the local signature golf course) and works "traditional" hours when not traveling. Just beginning his third year, he earns a bit less then D earned in her first year. But, his salary greatly exceeds his former baseball buds who graduated with business or econ degrees - because of his alma mater.
(For those interested, D is a typical IB analyst. A "light" week is 60 hours and represents about 25% of her time; a "typical" week is 70 - 75 hours (50% of the time) and a heavy week is 80+ (14 hr days, 7 days a week). A pace I certainly couldn't do, but a young ambitious person can. She is inundated with headhunters on a daily basis - she can ease up whenever she chooses in the next job; but, she has proved her capacity to give her employer whatever is needed.)
It is also difficult to project what a HS kid will want to do as an adult. A kid from Princeton can really choose from a huge, diverse menu of prospective careers and employers - even if in the middle of the class. Most other schools don't really provide that option.