The big two supermarkets in Australia use tablets attached to the trolley so the picker doesn't have to carry the PDT with them. The pickers, delivery drivers are all employees of the supermarkets. In areas where they have enough customers, they have 'stores' that are only for online fulfillment. You have to reserve a time slot, usually closer and more convenient equals more expensive. I once price checked the groceries compared to a receipt from shopping in person, and there was a 5% markup on items that weren't on promotion. You can 'click-and-collect' to save on delivery fees, but you still need to reserve a time slot well ahead, during the lock downs it wasn't unusual to have to book a week out.<p>I worked in a DC for one of the supermarkets and the pick rate is closer to 200 cartons per hour. Cartons contain multiple units and can be pretty heavy depending on the product. It's not for everyone, even with incentive paid on top of a healthy union wage, most people would quit after a few months. The good pickers made it look easy. Some had been working there 10, 20 years.