The student's have a right to use their money like they want. If they're happy studying & gambling because they're comfortable doing it they won't take advice from ppl it's some thing they'll understand when they're getting older.
The one who has money will decide how to use that money. If he is given any advice and if he does not accept it and says that how I spend my money is my personal matter, then there is nothing to say. He will make many mistakes at this age but those mistakes will not be seen by his consideration, but when he grows up and understands responsibility at some point, he may regret the mistakes he made in student life. However, when the time is up, there is no point in understanding, should understand well while you have time.
Students that are still dependant on their parents and guidance to pay tuition fees and survive don't have the right to use money given to them as they like. Unless the people that gives them money tells them to gamble with parts of it but I seriously doubt that any responsible parents or guidance will say such a thing. Dependants and unemployed people are not surposed to have anything to do with gambling because in the process of trying to win and double their money they can lose everything. It is only people that makes their own money that are qualified to gamble.