I believe that gambling winnings and rewards accumulations comes from the amount the gambler put in to wager with, so if you say that those who gamble with small amount of money can win big, you may have not entirely cover's the whole nitigrety of gambling and risk involvement, let say if I am staking a bet with 0.00001 bitcoin, and I want to win 0.01 bitcoin in total rewards, it then means that I will have to accumulate alot of gains so that the rewards can increase from the odds accumulated, but we should not forget that, the more games you accumulate, this s also increases your chances of losing the bet, because the higher the number of game's you accumulate the higher your risk level, so for sure if you think you can make huge amount of money from gambling with a small amount of fund's you have to rethink the risk you will face.
For me, it is better I gamble with just a big amount of money but on a single game and with low odds that increases my chances of winning the bet, although that is not also a guarantee to win either since gambling is filled with unexpected outcomes, so for me I gamble with at least a good amount of money if I intended to win something tangible, but if I am just gambling for fun, I don't mind using a small amount of money for my bet.
So that will depend on what is our reason for playing gambling. If you playing gambling for making money, you can use big money as your bet in one game but you will have a big risks to lose all of your money. You know that winning in gambling is not easy whether you use big or small money to bet so you must realizes about the risks. That is why when you playing gambling, you must have limitation to know your risks and prevents the risks becomes bigger.
For me, it is better I gamble with a small money in a limit time to prevents the risks of losing the money becomes bigger. I don't want to see the big lose so that is why I always limit myself when playing gambling. That will be the same for the rich or poor people who playing gambling because the more money they use to playing gambling, the bigger risks of losing the money they will get from gambling. So you must limits your money if you don't want to get a bigger lose because that means you attract the bigger risks of losing the money comes to you.