Do you think there is any measure through which the strange guy could be identified since there was no CCTV cameras stationed in and outside the shop environs?
Then again, for about getting him notified. I will say if he is regular customer then they should be able to know him when he comes except that very day was his first time and it would be hard to track him or even trace him, except there is someone that knows him there he may direct cashier to his home to get him arrested for not paying up his bills.
On the other hand, I am also quite curious about whether it was a new person who came to the store or a gambler who had subscribed or had often bet there, but at first glance I think he might be a new person who came there, because if he was a regular customer then he should not have run away, at least he said something to the cashier like he owed money and came back again someday to pay it because most likely the cashier must have recognized him. Regardless of whatever it is, I think in the end this is a valuable lesson for the cashier to be more vigilant and careful, and of course this is also a lesson for the store itself to improve security.