I think we hear about the bad stuff, some flight attendant or passenger complains, and the logical conclusion of a family with a crying baby is booted is the end result. My counter-anecdote is the exact opposite, my fourteen month old daughter cried the majority of our 3.5 hour return flight and she was quietest (not quiet but quietest) was when I was standing and holding her in the middle of the aisle. Any dirty looks, and I scanned for them occasionally, were non-existent (or I missed them and they never vocalized) and most people either had noise-cancelling headphones or just rolled with it. When we apologized for the noise there was a lot of "Oh ours our teenagers now, we've been there, you're ok!"
Some of it maybe the bigger stink they make the longer it all takes, but a lot of it is probably shared communal experiences. If some baby was wailing their lungs off next to me on a plane, I'd roll with it, the parent(s) is having a far tougher time of it then I am.