My graph is a partial representation of the supermarket and does not contain all the goods. It has just the stuff that I've bought at least once and manually positioned into the nodes. Sometimes the supermarket decides to relocate groups of goods and I have to update my graph again, but it does not happen too often (they do it probably once or twice a year)
An app that helps me with shopping at my main supermarket.
I usually go always to the same supermarket twice a week. I was frustrated that every time I changed something in my shopping list I had to mentally recompute the optimal path to pick up everything.
Now with my app I am able to build the graph of the entire supermarket (each node represents a rack with shopping items) and then given my shopping list it computes the optimal path from the entrance to the exit. It's a version of the classical travelling salesman problem