As noted by others, he's not saying bar, as in a place to get drinks, he's saying bear as in the animal.
The US is full of regional dialects and accents, and the narrator is supposed to be some kind of cowboy type. He speaks with a fairly thick Texas drawl, and the word bear just happens to sound like bar.
For example, take the Ka-Bar style of knife. The reason it's called a Ka-Bar? The company that makes this style of knife once received a letter from a fur trapper with testimony of how he used their knife to defend himself against a wounded bear that attacked him after his rifle jammed. The letter wasn't terribly legible, and of the fragments they could make out, "ka bar" was fairly easily understood to mean "kill a bear".
The bear is a metaphor for life, and the phrase thus generally means, "Sometimes you win at life, and sometimes you lose."