You hear it at check in all the time:
"Can I just check the size/weight of your carry on baggage?"
"It's the standard size/I take it on all my flights/I took it last week on this route/I am not checking in my valuables/I don't want it to get lost/I have a tight connection on the ground at the other end/I am a gold card holder, I can take what I want..."
Then there's the people who knowingly ignore the restriction sand check in online and waltz up to the gate with huge bags, either slipping them by the gate staff or kicking up a fuss about them being taken off them at such a late stage in the game, causing a delay to the boarding process.
Every excuse in the book is used so that people don't part with this hand luggage, but at the end of the day even if every passenger brings a small trolley bag which meets the airlines requirements perfectly there will still be problems on board the aircraft. Until someone steps in and draws a line which all airlines must stick to then we will continue to see confusion and delays due to hand baggage for years to come. The maximum restrictions currently in place are far too generous and should be bought down and then applied to everyone. Nothing more than a laptop bag or small backpack/holdall which is easily squashed to fit in to an overhead, not some rigid suitcase thing. Imagine a 23KG bag falling out of the overhead locker on a bumpy landing...that'd kill someone.
Edit:
Airline has ridiculously large cabin bag allowance-->experiences delays with cabin baggage problems on departure-->passenger satisfaction falls due to delays-->airline gets bad press due to poor passenger satisfaction-->Airline changes policy to only permit more sensible sizes-->passengers baggage checked more closely at gates and at check in-->causes longer lines, which cause delays and causes more bags to be taken off of passengers-->causing more harassment for ground staff-->passengers complain more about what they are having taken off them-->airline customer satisfaction falls-->airline gets bad press for taking peoples hand baggage off passengers (cue sob stories in the mail)-->airline re-introduces old policy of take whatever you want on board-->repeat process from the start!
Airlines, as usual, are damned if they do and damned if they don't.
