That's not the impression I hear from my many intentionally childless friends. They take the negative behavior - the screaming, tantrums, chaos - as the norm.
It sounds like you always wanted kids. I don't say this to criticize - it's great that those who want to start families do so - but I don't think your experience is universal.
Oh then it's even worse! As again, only the more well behaved kids are going out in public.