I've always been able to decline overdraft when opening a bank account in person. Banks argue the fee is preferable to the embarassment of having the transaction declined, but with how often credit cards flag fraud the embarrassment when it happens is practically zero.
Also, absolutely no one cares if your card is declined. They just wait for you to use a different card. If that cars doesn't work... Oh well. If it does work... Ok.
The "embarrassment" is completely made up.