I gotta say, taking credit cards is the best thing I’ve ever done. I pay 2.5% a transaction and that’s IT. Nothing else. My customers double up the order sometimese knowing they are going to swipe it. It didn’t just make me a few extra dollars in sales.. It made thousands of extra dollars in sales.  Though there are people out there that are old school, and if change would hurt them, & their routine then I wouldn’t suggest disrupting their flow.
 
Biker Jim, &  Trenton Dog are both of the same cut. They are BOTH street vendors. THey both sell from a cart. It’s mobile food. You are no different, Stop acting like you are, just b/c someone sells something different and NOT the plain jane same.
 
Thinking outside the box is what gets you noticed, and sometimes works to their benefit and to have every available option to get paid is KEY. I wouldn’t like it too much if a customer walked away b/c they didn’t have enough cash to cover their bill.