In conversations, editorials and articles about parenthood versus childfree- or childless-living, there's one accusation that I see repeatedly brought up: being selfish.
The irony is that it's an accusation lobbed against each of these groups of people equally for different reasons: against parents, against people who chose to live childfree, and against the childless who are struggling to conceive.
As a for instance: say a woman writes an article about the many reasons she has chosen a childfree life for herself and does not want to be a parent. In the comments on the article, that women will repeatedly, without fail, be accused of being "selfish" by some parents reading her piece. They will comment on her being "self-centered" and unwilling to give up her "carefree" lifestyle and make the necessary personal sacrifices in order to raise a child. Because, you see, these people feel that being a parent is the most "selfless" act a person can commit in life: giving up any and all other aspirations, financial goals, personal wishes, what-have-you for the benefit of raising their child. A childfree person, in their minds, is a person who is "too selfish" to want to make any sacrifices for the benefit of her (theoretical) child, a non-existent baby who apparently matters far more to the world than that woman on her own ever could.