Yeesh.
Someone sets up a big "Leave some money, take some money" bin on the counter at starbucks, lots of people participate, and you don't think someone is going to sit down, watch the bin, and when someone puts money in, walk up and talk some?
It's a "Leave some money, take some money" bin - it's not a "Only take some money under the following rules and conditions, 1) you won't do it often 2) you won't take much 3) you will honor the donation of others by using the money for whatever they felt its intended purpose was, even though everyone thinks of it differently, etc, etc, etc".
He didn't "steal" money, unless you also assume that the people who bought themselves a latte with it stole money.
It was a social experiment, and it ran its course with the predictable end.
There was no hacking - all they did was transfer funds from one card to another, which is perfectly legitimate according to starbucks TOS.
In fact, the only thing that was broken was starbuck rules about sharing cards - the original person who started the experiment was blatantly disregarding starbuck's terms of service for the card.
Moral of the story: Don't leave bins of money lying around where other human beings can get access to them and expect to be able to dictate how they use the bins of money.