This just crossed my mind and there's a possibility that this scenario exists in real life
Do You Think It's A Cause Of Concern For Your Employer if he finds out that you are a compulsive gambler and you are working in a department that deals with money, do you think it's right that he transfer you to another department that has nothing to do with money?
I've worked for companies that ask you not to engage in such behavior. I once worked for a small company owned by a Mormon who used to want to meet everyone's spouse and make sure that their entire living environment was in line with how they expected people to live. Very strange... I don't think this is typical, but I know it exists. Things like gambling, smoking, unhealthy eating, all were things that were not allowed to work for this company. I spent about 9 months there before deciding that it was more like a cult than an employer and decided to find something better.
So yes, I do think that there are employers who will use your personal choices in life against you, whether that be gambling or anything else they don't like.
That's something that you have to abide or you may lose your job. However, for OP, its better that one should be transferred into another department to avoid the future scenario. If you are really a compulsive gambler, then its hard to control that and you can do anything against your will for the sake of gambling. I think the employers only wish for the success of their companies and their staffs, so if you can follow their own rules, that will be much better as long as you are not being mistreated.