Circle K

I stop at this gas station at least 3 times a week because of proximity to my home and I travel a lot. Each time I need to get gas they always claim to never have cash? How is that possible for a gas station on such a busy road. I had a 100.00 and needed 40.00 is gas. How can you run a business and not have 60.00 I'm change in your drawer? It's a constant problem so I guess I will need to start spending my money on several gas purchases a week at a different station, maybe the Sheets that is across the street.