Yes, gambling can be considered wrong of it causes negative effect in your life or into the life of the gambler.
But we have the key to prevent it into being a wrong doing, we should consider to have a Limit and tolerance on the money that we bet and on the time that we spent when playing gambling games.
We should consider that gambling is made for dun and it will stay at that way, so that in the end gambling won't turn to be a wrong doing in your part.
I think If you think about gambling being fun it only apply to the rich ones and If the less fortunate people will apply this kind of thinking they will end up losing much and getting bankrupt and I think gambling is not fun at all for them, because of the money that gets involve in playing it.
But most certainly,people who play gambling games are the ones who are not poor and also there are few who are on average living that play gambling.
Most of the people I know personally that do play gambling games are the ones who have a money to put at stake, those who have a decent job and a decent salary.
And one more thing, If you try to search for the main purpose of gambling, It is said that it is for entertainment( Try it in google) so we should also treat it the way it was supposed to be, and not as a way to earn some extra money from it, as at that kind of thinking(playing for the money), you will tend to lose more rather than to win.
If those poor people desperately needs money, then they should have to look for a decent paying job, and not to put their money in a risk of losing it rather than doubling it.