Why some (most) individuals can't understand many people don't like kids?
Because they get brainwashed from religion, popular culture and social pressures from family and friends to think they are obligated to breed. To choose not to is like not having religion, it is seen as defective, pathological, anti-social and even unpatriotic.
Thank you for pointing out what I am saying since childhood. Everything but the religion part, and in Spanish, was said to me since ever.
Fortunately, I was born to an Atheist family and I was spared the religious part.