In a nutshell, they don't want to deal with the real world. It's incredibly rare to find someone who is able to disassociate what benefits him from what is actually good for the student. Far, far too many college counselors, teachers and professors are unable to do the same. In fact an entire industry of individuals has been created around one of the most evil scams of all time. I have even meet 'freelance college advisors', who were in their 20s. I'm still trying to conceptualize how a something like that can even exist. Think about that for a second, you have someone who is barely out of college themselves, advising an 18 year old on perhaps the most important decision of their life which is to go or not go to college.With the prospect of an unappealing, entry-level job on the horizon, life in college becomes increasingly idealized. They think graduate school will continue that romantic experience and enable them to stay in college forever as teacher-scholars.
Now giving advice, be it father/motherly or brotherly/sisterly isn't a bad thing; I did it for my brother and I like to think that it is why, when entering his college, he only considered accounting or engineering as his two choices and is now doing accounting. My problem is that college advisers, whose only experience is either being a student or a college advisor, is incredibly stupid because, due to their experience, every answer to every question will invariably end with them saying "You have to go to college" because they no one is going to pay someone to say "eh..maybe you shouldn't go to college. Maybe you should learn how to use a wrench instead." That would get them fired.