Indeed, having children should have tiny nickel and dime costs all throughout your life in a million different ways. It should be the norm that just trying to raise the next generation costs you time, energy, effort, and money just to do normal day to day things, and it should especially be harder for you because you dared to have children.

Wait, why is nobody having kids?

Generally you will be expected to pay for the costs of your life decisions.

The world has more than enough people, so we shouldn't be subsidizing having children. Imbalanced demographics can be solved in other ways.