This isn't with gambling alone. With each and everything there is positive as well as negative side. The way we use it and move forward gives it an positive as well as negative outlook. With gambling we can't state certain things to be positive and certain things as negative.
Why I say this, because one who has got lucky to win big describe on gambling as a positive thing. On the other side the losers will term it negative. In this manner same thing gets described inverse.
I agree with what you’ve said that everything has both ends and it’s either positive or negative/ good or bad side. It’s the way we perceive things and what we do with it gives the result and image of something, in this case - gambling. It really depends on someone’s point of view, experience, and knowledge on gambling what he/she would say about it.
Like the example you gave, the winners and losers. The way they would describe gambling’s side would be way too different from each other since they experienced it first-hand. Of course, the unfortunate ones would say something negative because they lost while the fortunate would tell positive things because they won.
Whether what between the good or bad side of gambling overcomes the opposite one, relies only on the gambler himself who experienced both.
Perception is indeed based on the person involved, and on what degree he is into gambling activities. And a lot of factors play on how he sees gambling. It may include his financial status in life, where he works, what type of environment he is in, married or single, early foundation in gambling like influence of family or friends, knowledge of the game/sports and many others. Some people will see its good side more than its bad side whereas, others will have total rejection in any form of gambling.
So I guess, just respect each player because we don't know where they are coming from, as long as you are not harming anyone, or they are not harming you, just co-exist peacefully.