Yeah, Gambling is not wrong if it is in limits, but if it becomes an addiction then one day you are gonna loose all your hard earned money and even bitcoins as gambling doesn't guarantees us success everytime, it is just a matter of luck, if you are lucky enough on that particular day, you can even hit the jackpot or else end up loosing.
That is right. There is no guaranty of winning gambling. The result is quite random and there is house edge against the gamblers. Most gamblers will lose eventually.