Correct, it does not make sense. At the time of surveying, there was a vending machine with coin slots, and stickers for Twint, Parkingpay and Easypark and a info sticker saying that the max stay is 30 min, and that 30 min is free. I suspect they simply want to make sure that people stay less than that 🤷. That, or they selling car reg data 😱