Vagabond: The reason is because philosophy allows for such diversity. And because it's a hard question to answer.
A job as a "philosopher" is damn near impossible; the closest to that one can get is becoming a professor at a university and write philosophical books. But the point of studying philosophy isn't to get a job as one. It's about the gratification of knowing (or attempting to know) your life and experiences. Plus along the way, you gain critical thinking and communication skills that no other field of study rivals.
Like your friend, I don't know what I want to do with my degree. But that's what life's journey is all about. Going into it knowing
exactly what you want to do disallows for adventurous opportunities. University is not for developing work skills; it's for becoming
educated.
And as an undergraduate, I might as well study something of which I take pleasure. I was a computer science major for two and a half years, and I hated every minute of it. Since becoming a philosophy major, I've changed so much in both my philosophy of life and my personality.
Plus when I master the core mechanics of something like logic, I can easily jump into programming if that's what I want to do. A win-win, if you ask me. And I can get into the ladies panties and stuff.
That's the other perspective.
Basically, if you want to go to college to learn knowledge that will be tangentially related to your future, definitely keep in mind what kinds of jobs you can get with your degree. If you go with one of the "real" majors (engineering comes to mind) you will still learn a lot of outright useless stuff, but you will also learn a lot of stuff that WILL be useful (if only to get the ability to figure out if the computer program is having a hiccup and giving you weird data). Just expect to feel pretty annoyed if you go into a different field, since you really won't have a use for trigonometry and all the other fun stuff.
If you are okay with working "normal" jobs (salesperson, office minion, etc), then learn to your heart's content. The "hippie" majors have a lot of really interesting classes, and facets of pretty much any career can be enhanced (to varying degrees). by the crap they teach.
And, of course, by "hippies" I mean the people who can actually tolerate all the academia-inspired "thinking" that comes out of this stuff. Not my cup of tea, but more power to you guys (more jobs for me :p).
And by "crap they teach", I mean "stuff". I just prefer to use the word crap, since it is a fun word.