I have been living outside of the "traditional" heterosexual male/female household structure for many years now. I am so used to this that I have forgotten much of what it means to live within this framework. Recently, while on vacation, I was in this "traditional" framework and looking through my current perspective shed some light on an annoying, artificial sex distinction.
In this setting, I had returned from a morning run, other people had woken up, and breakfast was being served. The person making the breakfast, a woman, fixed 5 plates of food. While doing so, she asked "The Men" if they wanted eggs with their pancakes. Onto the 2 men's plates she then scooped 2 pancakes and a pile of eggs, and onto the 3 women's plates, she scooped one single, solitary pancake.
It may be true that, due to their larger body masses, men on average have larger appetites than women. Yet, shouldn't who gets more food be made on an individual case-by-case basis that has more to do with hunger than sex parts? As a woman, I have a pretty big appetite. I am active, I work out a lot, and I burn more calories per day than most people, man or woman, do. That is, I need Man Food.
In short, the sex/gender binary and all of its associated stereotypes just don't work for many people. They lead to all kinds of annoying assumptions and expectations. In our society, men are encouarged to eat Man-Sized portions of Man Food, especially steaks and other animal products that keep him at the top of the food chain and that keep him big and strong. Women are still encouraged to eat small delicate portions of Woman Food that will keep them light, weak(?), and pleasing to the eye of the male human. Because women are dainty, female hunger takes a backseat to the inherently large appetite of male hunger.
It is in ways like this, small and large, that men are encouraged and expected to take up space. Thanks to the idea of gender complementarity that tells us that women are everything that men are not, the expectations for women are opposite to the ones for men. The assumptions and expectations surrounding women revolve around sacrifice, birdlike appetites, and subtle hints to not eventually take up too much space with our bodies. For instance, where many men will enter a subway train, sit down, open their newspapers, and spread their legs wide apart, not caring that they enter another person's seat space, many women will sit down, shrink, and take extra care not to enter encroach on another person's limited space.
Many men are entitled because they live in a society where people, men and women alike, cater to their entitlement. What is in actuality rude behavior, such as a skinny man forcing his legs into your seat-space, gets passed off as Boys Being Boys' inherent nature. Resist. Push back. Then go back for seconds.