Why should a passenger need to carry that much coinage?
There's a lesson in this for me - I wasn't clear enough. May I rephrase?
Have you ever carried that amount of coinage? Do you know how much it weighs?
If £60 isn't sufficient shouldn't the airline(s) decide what is?
The airline has decided - It's £60. Apparently there is a belief that this isn't sufficient. It seems reasonable to ask what might be considered sufficient if that is the case.