Drinking especially quaffing drinks, my tummy accepts more of everything, and so I eat and drink to fill it.
When I'm not drinking, my tummy doesn't swell and I don't try and fill it.
Some how I feel it is a mix of lost inhibitions and stretched stomach linings.
Not an expert but I do know that when I drink I put on weight and eat heaps more, during drinking, after and the next day trying to recover minerals and vitamins.
That's a lot more eating than normal.
My personal answer is, choose smaller less, alcoholic drinks or non alc. Believe it, after a few minutes your friends won't even notice.