Why thief???
You give MVitaliyB money, and hi not return their... BAD PERSON - not thief!!!
Malfunctioning ATM takes guy's debit card. Guy at ATM parks and goes into the office to talk to tellers. You pull up and see his account still up - and there's the "Quick Withdraw - $300" button on the screen. Is it not theft if he "gives" it to you by accident when you click the button to take what you know is his?