If gambling is something the students do for leisure it is going to become normal. There is a difference in gambling with students in a card game for fun and going to a casino or internet casino to gamble. They can gamble like it is a normal thing to do but when they are students it is not normal, they should pay attention to studies and dream about a beautiful future.
Young students who get pocket money from parents shouldn't think about gambling. In poor countries parent can't educate children with out suffering. If they start gambling they'll betray their parents it isn't fair they've got to graduate & help their family.
Those who do anything unfair are not aware of that, and they do not think about the things they are doing. If they are aware that it is unfair, then they would not engage with anything like gambling and/or drinking. Actually, they usually do something that is not fair, but unconsciously.