Eminybob "Someone having a peaceful quiet drink and not disturbing anyone is fine and normal.
The smell is neither here nor there, there are much worse smells to be encountered on trains IME."
You could also say someone having a peaceful vindaloo curry is neither here nor there. Just because someone opening 100 cans of beer sitting on their own doesn't bother YOU personally, doesn't mean others aren't bothered by it, and likewise just because you think it's peaceful doesn't mean others find it so- likewise with the pungent smell.
Just because there are worse smells does that make it okay? By that argument, I could put you in a sewer & say "it's fine because there are worse smells such as dead corpses". ;)
I could also put my crying child in your ear hole & say "it's fine because there are worse sounds".
Anti social behaviour is only anti social if enough people are bothered by it & it sounds from this thread like I'm not alone.
I love to drink- but on a night out where I'm careful not to bother anyone. This wouldn't translate to a long train journey surrounded by travellers unless I was very inconsiderate of others or unaware of others (both similar problems).