Government employess are public entities. They are paid by the citizen so they should act morally. So government employee should barred themselves in gambling vicinities and the rule of not letting them to enter helps a lot. But the sad thing is, corruption is every where, the one that should implement rules and apply it are the one breaking them and restraining them. I hope any government officials or authority involved in or committing illegal stuff be publicly executed to serve as an example.
Yes, taxpayers are paying for their salaries and that's why they have that oath-taking that they shouldn't be found anywhere in a physical casino. That's against the moral values that they promised before they accepted their duty.
Corruption is like an accepted thing for most countries, no way to eradicate it unless from top to bottom officials have been cleansed and replaced with officials that are valuing their moral conduct.