This is true for any sort of sacrifice. Volunteering, saving people from burning buildings, giving your last dollar to someone more in need.

To be clear, I look at my children in the way you describe. I don't hold "my sacrifices" over their heads, it was a decision I made happily and don't regret. Same as when I donate money, help someone on the street, etc. But IMO just because it's a decision (even made happily) doesn't mean it's not a sacrifice at the same time.