Believe it or not, this question has not been answered concretely. My suggestions do not measure up as an answer, but I can assure you that this habit has nothing to do with gender or any type of beer-loving-gene.
Every time I visit a bar or a pub, I see a few bros drinking the fizzy drink. Of course, I've also seen business partners (and the like) share a bottle of wine. However, these wine drinkers are normally dressed in suits while sharing this romantic beverage. So, that must be the thing: men drink beer because everything and everyone tells them that it is the manly thing to do (without having to wear a suit every time).
I've inquired why men like beer so much and they gave me some lame responses, such as: "it is the most hydrating" or "it is what we do when we watch games." Obviously. The answer they are avoiding is: beer is a socially accepted standard between men; and they are simply afraid to appear less masculine (men will never admit fear).
Based on this preliminary observation, I propose that men drink beer because...
1) Men are conditioned to do it: ever since they are boys, they are exposed to advertisements all over the place in the same way that girls are exposed to thin thighs and Kim Kardashian's boobs. These ads showcase beer half the time and contribute to the man's internalization of cultural meanings, interpretations and values. Porno can also fall under this category and probably cologne as well.
2) It is easy to drink and because men also like to drive cars, beer allows them to slow down the pace of their drinking. As we know, beer normally comes in super-size-me jugs.
3) It is the "bro" thing to do and because a man's identity revolves around his money and how manly he dresses, smells and feels, beer naturally falls into his 'top 10 cocktails.'
4) Beer is kind of good for doing business (and men love doing business!). When you meet with your boss, you won't order vodka shots. But you will order a beer to, ironically, look more professional.
5) It allows men to get into debates over whether Heineken or Stella tastes better and to try to figure out what their current beer of choice says about them (kind of like how women match their misfortunes to Cosmo horoscopes). A(n)
6) Beer is good to marinate meat with and to have with chicken wings. Because men, being the cave-like creatures that they are, love red meat, it is only normal that beer is paired with animal slaying. Beer is also good for passing kidney stones and washing hair. Just and FYI.
7) When men need to "talk" they don't say "let's go out for coffee." Beer makes all men problems better.
Taking all these things into consideration, it is now more clear as to why men have such an attitude towards beer drinking. Eventually, having a beer becomes a normal habit and a staple for bro-gathering and at-home relaxation.