[What if everything is on direct debits and working nicely, but one month your workplace screws up the payments, could you lawfully pass the charges to them?

I think it's easier to see what you have in your hand, thus it's easier to manage your money. Checking your account takes time (OK, around 3 minutes from my internet connection or a similar amount of time if I'm first at a cash machine) and people will try to remember how much they've got, and occasionally fail.

If the banks carry on doing this, fair enough. But £25 for every withdrawal (HSBC) seems excessive...

Once upon a time if you ran out of money it meant your wallet was empty, now it means that your wallet has a hole in the bottom where the bank has extended it without asking. If I have run out of money, don't let anyone take anymore out! I'll deal with my landlord asking why the rent hasn't come yet or British Gas asking why I've not paid for my electricity. If I have no more left don't let me take money out of the cash machine or buy something from the supermarket, tell the cashier "No, this person has no money left!"

In the end having a small permanent overdraft facility on your account stops 99% of any charges