There is the somewhat true saying that, if a foreigner wants to make a small fortune in Thailand, he needs to bring a big one. This seems to be the general consensus among 'farangs' in the know, and it is true especially for running a Bar Beer. (Adjectives or pronouns are put behind the noun in Thai, therefore it is not a Beer Bar but a Bar Beer.) This is in essence a small, open-air place which has a few bar stools and sells beer. One can find them almost everywhere.
I added a few pictures of the many failed Bar Beers, one can run into; I call them the 'Bar Beer Ghosts'. And yes, some of them are really scary, too.
I don't think that anyone makes any money on a bar like this, no matter what the design of the business plan looks like.
But it is part of the Thai popular culture and that is why I appreciate the risk takers opening, and/or running one.