Well i guess the biggest reason for this is selfishness. When you gamble you will first be like no no and stuff and then slowly you will invest in the site and then see that if this happens correctly i will get so so money. But most of us don't realize the fact that there is a high chance of losing and we simply just put the money on the bet and lose it and be like i i will never invest again. But we again get jealous of the return and invest again and or the reason of investing again is seeing proofs of other people making 1000's of $$. Well to get addicted to it you just have to control yourself