The warehouse barcode scanner appeared to be a wireless Symbol or MetroLogic/Honeywell. These wireless barcode scanners can be programmed to emulate a carriage return (same as if you pressed the enter key on the computers keyboard) after each item is scanner.
Not sure if this is a classic "not knowing the capabilities of your point of sale system moment" or an "edited for reality TV" moment. I will be contacting O'Neills Clothing to make sure that the problem was resolved (I'm assuming it was since this episode was likely filmed several months ago).
Are you in the US and in need of no cost retail point of sale advice? I'm happy to help and can be reached on my cell at 208-340-5632 (mountain time) or via email at firstname.lastname@example.org.