This is a classic example of we vs. them, I guess there will always be people with kids who think the same as you so it might not only be about perspective. My conclusion is that kids are their own beings and they are prone to behaviours that is not the norm in society, we all just have to adjust to that, you can't really reason with children.

I find that being sleepless and being hungery affects my mood a lot, I believe these are things that families can have a hard time regulating, so my bar for the expected behaviour from families is set a lot lower than for young adults. Just because I know they have a hard time.

Sure obnoxious people get families too so there is always a chance that they really are entitled.