The commercial above pokes fun at the cultural idea that women go to the bathroom in pairs, sometimes even in a group. The spot above uses men as the point of comic relief.
A man (named Phil) has his man card in jeopardy when his friends point out that he already has two strikes against him for actions deemed unmanly. Phil’s first strike was asking a buddy to join him in the bathroom. Yes, in our culture going to the restroom in groups is considered to be a "girl thing," though I do have to question why any guy would express nervousness at going to a public bathroom? His second strike, not drinking a Miller Lite of course.
I believe the ad agency is DraftFCB.