Dear Rabbi Kornfeld,
The Gemara describes the third group to go into the Beis Hamikdash as Kat Atzlonim. The reason is that although **somebody** has to be last, it should not be you. The Gemara supports this by the statement that some people are spice merchants and some tanners; better to be a spice merchant. Further, the world needs males and females, better that your children be male. The first is a valid proof, i.e. that although it is a necessary evil, you personally should avoid that evil. How can a person avoid having female children?
It seems that the Gemara is not teaching *practice*, how one should conduct himself (e.g., to not become a tanner, to not give birth to females), but rather it is teaching *gratitude* for what one has; that is, there are some people who become depressed because all of their children are males and they have no females, because they would prefer female children since they are easier to raise, they help within the household and they help raise the other children, etc., and therefore the Gemara says that such a person should not be distressed that he has no female children, but rather "happy is the person whose children are males," and thus he should accept his lot with happiness. Similarly, happy is the one whose profession is that of a spice merchant, even though he does not profit as much as a tanner (since he has such an easy job).