I have to ask because I'm not familiar with the Russian expression: is this a general description of someone (as in Galia's translation) or does it refer to someone thinking that drinking is a good idea at a specific occasion (as in Elena's translation)?

It means he didn't miss an occasion to drink

Elena, there's the perfect translation. You should post that instead of that KEEN one. Keen is used in specific situations.

Yes, I thought about it too already)

++Galia & Elena