If this is the way you want to play, then go for it. It's basically akin to gambling/thrillseeking though, and won't likely develop your poker skills past a certain point. Just as long as you are aware of this and are fine with it, and are also aware that the odds
of making a huge cash in this manner are pretty slim, then just go for it and have fun.
A problem comes though if you do eventually make your big cash. So you'll have $10,000 in your account, and the only experience you have is by being a master of freerolls and a handful of MTT. What will you do with your newly acquired bankroll? If you start playing higher stakes then what your skill and experience dictates, you will likely end up losing ALL of it for naught. If you just withdraw it from your account and use it for your life then it may be worthwhile. But really, once you start working, you will realize that $10,000 is nice to have, but in the grand scheme of things is really not that much money.
What happens when you work your way up the ladder stakes with appropriate BRM is that you gain a ton of experience along the way, which then makes you fit to compete and have a higher probability of winning when the stakes really are significant to your personal finances.
As you are only 18 and likely have never worked a full-time job, let me tell you that $10,000 is nice, but if money is the only thing you want out of it there are easier ways to get it (like getting a good job). If you can make something like 50-60k a year, as a bachelor with little responsibility, you can probably afford at least 5-10k a year as completely expendable income.
I think this kind of belies an important aspect of poker though -- poker is a game that we play for different reasons. Some of us play for the fun of competition. Some play just to gamble and thrill seek. Some play as a hobby and for side income. Some play for a living. Playing for each of these reasons has benefits and detractors, and really there's no ONE way to play that is right for everyone.