Gambling happens because people decide for them selves to gamble so they are making them selves sick if you ask me.
Right, gambling is sickness for addicted persons, but for normal persons gambling is not sickness, like you and me, gambling is fun and it is made for especially fun and give the people entertainment. But gambling become sickness for those kind of people who can't control ourselves and they don't care what the result if they lose in gambling.
imagine when you get started losing so much money feel frustated and start doing nosense things.
even causing a suicide because really not few people who gamble from loan money , and they cannot payback just the loan getting bigger and bigger.
first time, that person is normal and just play gambling like other people, and after time to time and that person gets much of winning, then that person become to addicted of gambling because that person can win much of money, then finally that person become more addicted until no one can control that person to stop gambling.
but for me, i think addicted of gambling is not sickness but its only situations that we only think and act for gambling, nothing we want to do beside gambling and its a bad habit for that person and its should be help by the family for the closest person and the friends of that person. if its necessary, we need called or bring that person into some rehabilitions to help that person.