Since when did studying mean dedicating 100% of your time to it? and the same can be said about having fun; do you just have fun and spend time with your friends 100% of the time? There's a thing called compromising, and it's quite a useful thing to learn early on in life.
I've been studying for 3.5 years now, and I'll get my degree in about a year, yet I haven't missed out on any fun with friends and family. In fact, I had a wonderful time so far, met lots of new people and even spent half a year studying abroad, how is that a waste of time and an outlook into a boring life ahead?
If all you do is study, then one day you'll wake up and miss the fun days, but if all you do is have fun, you'll wake up one day and head to the supermarket to bag my groceries (no offense.) I don't see the purpose in that really.
Studying opens up your world, and life doesn't end with a full-time job.