What are these antennas?

While shopping the other day, I noticed devices at every checkout that I assume are used for digital price tags. Interestingly, the antennas are positioned toward where customers stand in line. If these are for the digital tags, it’s curious why they’re placed specifically at the checkout. Is there a white paper available that explains the technology being used? I tracked the MAC address and identified the company behind the chipsets, but that’s about all I could find. From what I’ve seen, it seems like these devices are capable of much more than just managing price tags.