There are reasons for burger shacks to NOT have chargers, for EVs and phones alike: restaurants make money by maximizing customer throughput. Excuses for customers to extend stays is damaging to them.
There are other types of businesses, such as high end restaurants and furniture stores, that benefit from customers extending times in the store. Burger shops aren't one of those.
I've literally driven past restaurants on road trips because there was nowhere to charge close by.
It's not whether I stay for a long time or not, it's whether I come in AT ALL. The map on my car shows be both restaurants and chargers, as do many EV-specific charging map apps. I just filter by "food+charging" and the rest might as well not exist for me.
Similarly I have family and friends with serious food allergies: If the restaurant isn't disclosing allergens in their menu up front and says "ask the staff", we go somewhere else instead of playing 20 questions with the waiter after parking and getting seated - and then discovering they have no idea what "actually gluten free" means.
And you don't charge an EV to 100% every time you stop, it's basic chemistry and physics. The last 20% takes as long to charge as the first 80%. A 20 minute stop at a burger shack's 300kW charger will easily give a modern EV tens of percent of extra charge (100km+) while people eat.
There are other types of businesses, such as high end restaurants and furniture stores, that benefit from customers extending times in the store. Burger shops aren't one of those.