Most people don't understand the basics of statistics and blame everything on "unfair games". Gambler's ruin theorem is known for many centuries and it's really simple - in the long run player with smaller bank will lose. That's why all casinos pursue giant bankrolls and like to take investments.
I don't think with big bankroll we can beat casino and i think small or big bankroll to start gambling is have same chance to win. for example you can start to bet with 5% from your bankroll so you have chance win more big than you start with 20% from your bankroll.