So really, what you are saying, is that you are selfish and can't possibly fathom why you would spend time/money on anybody else but yourself, or maybe some trinkets for others in your life.
Wonder what would have happened if your parents had been so selfish. This is the GenX/Y'ers everybody, ME ME ME ME ME.
As far as not having kids well into your 30s, I think that's a very poor decision. After having our own issues with having kids we both wished we would have started over. By the time a woman hits 35-37, fertility drops fast.
I know many women who were career focused that ultimately regret not having kids, every one of them. At the end of their lives they have nothing to show for it.
On the other hand, I think it is far less likely that you'll find a parent who had the means and ability to raise a kid, that did, and that regretted it.
I took my two kids to the zoo yesterday with my mom. My wife is out of town and my dad just recently died. I could tell my mom loved every minute of it, especially when my 2.5yr old almost blew up with excitement seeing a polar bear just across the glass from him doing backflips in the water. My parents could have traded kids for a much better life, but then would she had seen that?
You'll understand in a decade or two, but by then it'll probably be too late.