Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

Are PINs always needed for paying with card?
For the first part of your question; Refer to related question  Why do some online stores not ask for the 3-digit code on the back of my credit card? The other case of Airport ticket machines, requires the physical presence of card. The assumption is that if you had the card before and after the transaction, it was you who used it for transaction. As the amounts are small its really easy by anyone [merchant, Banks] to write this off. The only way to misuse would be if you lost the card and someone used it. Also these ticket machines would have built in feature where by you cannot buy more than "X" tickets for the day. Ensuring max loss on a stolen card is limited to a small amount.