Gambling can't make anyone rich or I think it's very hard to gain profit by gambling. I think gambling is just a time pass. I gamble on my off-time.But, I think it entertained us. And it's not a waste of time in this matter.Again, if some one choose only gambling to increase his btc then he is wasting his time.
Technically, it is impossible to profit out of gambling. Most of the online gambling sites (such as PrimeDice) are having a house advantage, ranging from 1% to 5%. So, you are going to win only around 45% to 49% of your bets. And in my four years here in Bitcointalk, I have not seen anyone claiming that they have profited out of gambling.
Its impossible to earn profits from gambling, majority of user will loose in long run and even if they win, I am sure they will get greedy and gamble more and will loose everything at the end of the day.