What I want to know is did they let him have the cakes after all that? (since there was no one there with him who had cash and all)
Since the article states that he was rumbled, we know that he didn't get by with his plan.
I doubt that Tesco or the school allowed him the fruits of his deviousness, as that would have sent the wrong message.
My guess is that his mum makes sure to pack him an extra-size lunch every day from now on so that he won't be tempted to try this again :-)