Overgate puts an end to the game or the “profession” of not paying the bill.
Photocells authorize entrance and, without hesitation, block attempted exits of shoplifters, activating alarms, closing arms and warning that something strange is happening.
Photocells, yes. Because we use them a lot, because they are useful ...for every occasion.
They open the door, but also set off an alarm in case anyone attempts any extravagant exits.
They understand that you have transited and take note of it.
They also understand if you cannot find the receipt and keep the gate open long enough for you to find it. And they hardly ever make a mistake.