I mean lets face it, someone who is literally saving 50% of their income (and doesn't have a very low income) either has some sort of plan for it or is kind of dumb. The point of earning the money is to spend it on *something*. That could be saving for an early retirement (which requires a lot since you have both less time to earn interest and more time to spend it), saving to send the kids to college, saving to buy a life-size 737 flight simulator, whatever.
Saving that much just because "saving is good" is just going to end up meaning that instead of wasting your money on little bits of dumb shit, you will waste money one one big piece of dumb shit. Either way, you are still spending your money on dumb shit that gives you enjoyment but if you are sacrificing enjoyment in order to save heavily with no goal, you are just going to have a big pile of savings burning a hole in your pocket end up with a house on an island somewhere that it turns out you only end up using for one weekend a year (when you could spent the previous years spending a week on a different island every year with the same money).
well, yes and no.
Many young people don't realize how much even a basic life in retirement costs, and therefore don't plan properly. This is partly why many baby boomers are working late in their 60s and even 70s to try to make up for shortfalls earlier in their career. I don't intend to be one of those people, so I save more now.
That said, between my early 20s and now, I've gradually come around to the "you can't take it with you, enjoy it while you are young" mentality, so I've become a bit less frugal.