I've been in the software development industry for 19 years. It has been my experience that professional programmers who also program as a hobby are typically the better programmers.

When I interview candidates, I always ask how they got started in software development. I give bonus points to those who respond that it was a hobby first.

Your post varied greatly in direction but I'll try to respond to what I think are the main points.

Quote: but what's the worth of a college education if you never will work for a professional company, and actually be paid for your worth?

As others have mentioned, getting your "dream job" (presumably making games) right out of college is difficult. Hobby/Independent projects are a good way to bridge the gap between doing what you have to do to earn money and doing what you want to do. In the process, you improve your skills, generate valuable portfolio material, keep your dream alive, and potentially build a sucessful product.

Quote: I know some of the college students or graduates here, even though have the education, still have mediocre art.

There is no substitute for ability, no matter where or how you acquire it. Some of the best people I've worked with never went to college and some of the worst graduated from prestigious universities.

Skill in any area is a combination of how much talent you have and how hard you work. You can compensate for a lack of one with an abundance of the other up to a point. There are, however, people who are going to remain mediocre no matter how many classes they take and how much they practice and there are going to be those who produce brilliant work with minimal effort.

Most people fall in the middle of those two extremes and college, combined with a willingess to work, often provides the boost one needs to become truly skilled. Recognizing this, companies look for people with degrees. They are not, however, going to turn away someone exceptional because they never went to college and I can't think of a better way to show them "exceptional" than with independent/hobby work.

Quote: Which brings me on another thing I see on the forums, and that is people looking for mentors or tutors on the Help Wanted. Yes you can try and probably find someone more experienced, but are they technically a professional in the industry?

Teaching is a skill unto itself. Certainly a tecaher needs some level of competence in what they teach but it is a common misconception that an industry's best practicioners make the best teachers. For me, as a programmer, It would be an ego boost to be taught by John Carmack, but there is no gurantee he'd be a great teacher. He might be, but the skill to teach isn't instantly granted to industry professionals.

Quote: So I would like to end at the point that, maybe if you just an artist in your freetime and love working with other hobbyists, it's might be okay, but are you really looking for a better opportunity?

The motivations for working on independent/hobby projects are diverse.

Some people want to work for someone else and apply for jobs while they build a portfolio to show potential employers.

Others want to make games (or animated movies, or whatever) on their own terms and, lacking the cash to start a legitimate business, turn to independent work as a means to produce.

Others love to make games but acqurie other responsibilities (such as raising a family) that prompts them to take other, higher paying jobs, and turn to hobby projects as a way to do what they love in a limited fashion.

In the end, (like everything else) the decision to work on hobby projects is a personal one, but if you find yourself in a situation where you do not have your dream job, I can't see hobby work hurting you.