Where can I find a map of where in the US I can use shell rewards? Seems like it doesn’t work at shell locations in a city. However I tried using in a small town in Utah and it didn’t either work.
You can't. That is, Fuel Rewards app will show you a map with participating stations, but whether points from a particular partner would work there or not, depends on each partner. So, points from Stop&Shop generally work in states with S&S presence; points from Giant Food would work in states with Giant presence (except for PA, which is split between Giant Food and Giant Food Stores, separate chains, the latter not linking to FR), and they would also work in each other's territory once linked to FR account (but otherwise they don't). In addition, there are some areas where FR does not have a local exclusive grocery partner, where the above mentioned points would work too, but the only way to know is to look at the map in the app and see if discount applies, and even that is frequently inaccurate. They do work in parts of FL and parts of UT, for example.