Some people always get this wrong, not everything is relating to a spiritual issue especially gambling, it's more relating to a mental issue than something spiritual for instance you shouldn't be referring an addicted gambler to the church or spiritual home for prayers, rather such cases should be handled by a mental health practitioner, psychologist or the rightful professionals to handle the situation, your spiritual leader or teacher is just a religious leader meant to handle spiritual cases and not the right one to handle such cases, I don't know about other societies but I've seen people in my region make such errors and it needs to be addressed.
There are some extent that needs prayers mate. Yes gambling addiction is not related to spiritual, but you may need some spiritual help to assist in both prayers for the affected person. Someone addicted to the extent that he lost all his life to gambling or may be someone who planned to kill himself because of loss, should be prayed for and consoled. I know my own analogy might be a bit different from many others here on this thread but you can combine different hands to help an addicted individual. Addiction is a physical effect but to some extent might need a spiritual help..