When we play gambling, than it is normal that we become greedy. Because everyone play gambling to earn money and in this way, if we become greedy than sometime we win in behalf of our greediness.
It's human greed that always not satisfy , everty time we want more and more so it's endless and will keep happen for next cycle of life.
For some people who play for fun, I think they still able to control their greed ( based on their economy, religion behalf,environment, etc )
At the end only yourself that control whenever to keep gamble or not
yes that is very right to say and there is nothing wrong to say about this, in fact human nature is greedy and he want to make more and more and more and there is no end of human greed.