Then why will so few of them admit it? I have a theory.
You just admitted it, but this is an anonymous forum. Your kids will never find out you occasionally felt this way, and that's a good thing. But I think that our society is so invested in perpetuating this culture of parenthood that they hide the truth from young couples until it's too late. They imply that you're not a family without kids, that kids are wonderful, and invariably worth any minor occasional inconvenience or expense.
Because misery loves company. People have kids and find out how expensive and exhausting it is, then they look around at their child-free peers and are envious of the carefree lifestyle. They got "tricked" into having kids, so they want others to be as miserable as they are. So they NEVER admit any shred of regret.
"Kids are the best thing we ever did."
"Really? That one just pooped on your couch."
"Doesn't matter, still worth it when she smiles. You should have some."
Ever read
Scary Mommy? Some of those women are literally bordering on suicide and violence. Some of their stories are heartbreaking, about how financially crushing their child is, how much of a disappointment they are, or how much they regret giving in to their spouse and having kids (or being a little too loosey-goosey with the birth control).
Besides, the world is already way too overcrowded. We're clogging the skies with CO2, the oceans with oil, and the cities with hungry people who insist on free-range organic everything while we simultaneously turn our farmlands into condos and our forests into pastures. We've drained the oceans of fish, there's perpetual war in that desolate sandbox known as the "Middle East," the economy sucks, national debt is through the roof... are you really doing a baby a favour bringing it into this world?