Alcohol temporarily halts sugar metabolism as the body views it as a digestible poison and grants alcohol digestive priority. Sugars not metabolized by the liver must either be pissed out or stored as fat, but passing excess sugars to the kidneys takes time all the while the priority for the kidneys is passing alcohol not metabolized by the liver using as much stored water as it takes.
The same way pizza and bread make you fat. I tried anything from wine to vodka, if I drink enough to get drunk, unless I compensate with a really good food diet and a ton of workout, I will gain weight. What makes you gain weight is not just the raw calories but relative to food, it is very efficient in delivering most of those calories to your blood.
If calorie intake is 1 and calorie burn is also 1, you have 0 surplus calories. Let's say you have 1 extra calorie (keeping it simple) , the source is important. Alcohol > sugar > oil > bread/carb foods > veggies/fiber,etc... in terms of how much of that 1 cal your body can extract and convert to fat for long term storage.
I didn't even consider beer alcoholism. It would still have to be just bad eating habits, though. I know skinny people who drink several litters beer a day and the fatsos whole like this stuff have always been somewhat big. It's not the alcohol, no
What on god's-green-earth kind of beers are these? A pint is usually between 200/250 - strong beer (10%) usually hit's in the 350 range - but are you really saying that's normal at a bar?