I believe that's within their delivery radius

In the US our store delivery areas are not based on mileage. They are based on drive time, so in a busy city store it may only be 1 mile where as a rural store may 6–7 miles. Most stores will have a maximum drive time of 9 minutes and large percentage is closer to a 7 minute drive time. Drive times are calculated at moderate traffic times and at the posted speed limit when traffic allows it. In addition the delivery areas may not be a perfect radius from the store as another store could have better drive times due to traffic flows.