Someone should really do research on guys like this. I meet old dudes all the time who smoke like chimneys and drink like fish, yet they're older and more fit and mentally sharp than my grandma who'd maybe have two glasses of wine a week. There's gotta be some genetic thing going on here, we need to ID this DNA sequence so we can create a new humanity that can abuse toxic substances all they want with minimal negative affect on their health.
Besides genes, it could be that guys like the dudes you mention keep an active social circle (by drinking together every couple of days) so they're offsetting the negative effects of loneliness