Yes they are... but with adults one can take it up with them directly OR, if necessary - with cabin crew. if they are truly disturbing others or behaving inappropriately one should reasonably expect action to be taken...

With crying infants - no matter how long it goes on - one is (apparently) meant to just suck it up... Any complaint about it here on FT seems to lead to the question "How do you expect the parents to prevent it" etc etc..

Sorry..... Pardon the lack of empathy.....Not my problem. I didn't bring the poor little unhappy baby onto the plane OK?

You did. Responsibility rests... where????

Having said that... I must agree that the increase in Infant travel costs does seem........ disproportionate!