As with anything, there are positives and negatives. The rule is to be good at taking advantage of it in every situation we encounter.
Assessing the positives of gambling, there are many things it could offer.
- Discipline in managing money and accounts
- Concentration
- It could become a career; if you enjoy it so much, you could become a casino operator or, who knows, maybe even a casino owner (and thus turn it into a job)
- Meeting new people
- In rare cases, a big win could change your life
- Learning from the mistakes of others so you don't make them

The positives are numerous; you just need to change your perspective.
Anything done with a certain balance isn't harmful.