Having brothers you can't stand unless you can't stand. TFM.

This is funny because, as in most sizeable organizations, it is a near certainty that certain members of a fraternity will intensely dislike each other due to personality conflicts, grudges, and other disharmonious circumstances. However alcohol, due to its effectiveness as a social lubricant, has the potential to make this lingering animosity seem unimportant during the period of intoxication. The poster is suggesting that there are a number of fellow brothers in his fraternity with whom he has no desire to socialize with under normal circumstances, but with which he will socialize if is so intoxicated that his motor skills are sufficiently impaired to make it impossible for him to stand upright.