I have an idea that if you peeked at the financials for Casey's or any other modern quick stop, you would see that their profits on the sale of fuel are small when compared to sales of slurpees, snacks, trinkets, scratchers, & etc. I think back to the stations of my youth and about all they sold was gas, tires, oil, and fan belts. Some of the forward looking ones had a pop machine and a small candy display at the front counter where you paid for your fuel. Oh, they also had a free water fountain. Seems like the quick stops of today have replaced the old filling stations and fuel sales there are just a way to get folks in the convenience store. So too with EV chargers. Zip-Trip along the Interstate about 150 miles away has six chargers somewhat close to their gas pumps. Handy for folks charging as they can come use the restrooms and load up on the profit makers sold in the convenience store.
Also, I think you might be off on your average recharge time as if you are really concerned about making the best time, you will time your stops to be more frequent and charge more during the hungry part of the battery capacity. With the 250 KW chargers, 10 to 15 minutes gives you the most bang for your time. Newer 350 KW chargers will get you into the 6 to 10 minute range.