Aside from the embarrassment Kenoi's "partying' brings to himself and his county, drinking to the point of incapacity is selfish and irresponsible.

What if there had been an earthquake, tsunami, flood, fire or other disaster on the Big Island while Kenoi was in a drunken stupor or badly hung-over? What if he was disruptive or unable to think clearly or communicate reasonable decisions during a crisis?  Why should responsible officials have to deal with a crisis and a drunk mayor?  What if these other officials got blind drunk too ("it's a free country")? Who would make decisions? 

Being a mayor or other official is not a licence to do whatever you feel like doing. It comes with unusual powers and a corresponding burden of 24-7 responsibility for public welfare and safety. Clearly, Billy has lost sight of this. If he doesn't want these responsibilities, maybe he should just resign (and maybe check in to rehab).