The best way to earn Bitcoins are buying bitcoins with real money or gambling.
The more real money you invest the more money you can make of bitcoin.
Bitcoin is real money!! But you are correct, the more you invest, the more you will make with Bitcoin. There is a large calling for bitcoin out there and the more people that know about it, the more they will use it, boosting the price up. I do vote to stay away from gambling because you are never guaranteed to get nothing and you always risk loosing everything.