The phone shops I see are generally mixed in with other shops. Generally they are $3-$5 when you can find them. As for 'wouldn't pay to do site shopping', obviously you go into town for personal errands from time to time. Most towns have gas stations, fast food places, some chain retailers, banks and similar businesses. These are the kinds of places that are shopped most frequently, so unless you are completely self sufficient 40 miles from town, my guess is that there are times and opportunities for you to do shops.