Obviously it's important.
In gambling you shouldn't gamble too short or too long, if you gamble too short, you will not enjoy it. If you gamble too long, it consume much more time and you might feel bored.
People have to learn to manage their money, let's say someone work and get paid for $1,000 per month, but he usually gets $50-$100 every week as a bonus. He might manage his $1,000 salary and he should manage the $50-$100 bonus the same way he manage his monthly salary instead of spend all the $50-$100 for entertainment.
Yes, true, but I think in my whole life I have always seen gamblers manage money badly, they always get carried away
Then I would like to say, if you learn to manage money it will not only be useful in betting, in my opinion this skill will also be useful in normal everyday life.