Another reason they are kind of pricey is because they have to either buy the shoe or order the shoes. TOMS are not the cheapest shoes. I own a couple of pairs and for what they are, they are kind of expensive. So take into consideration that the painter is buying a shoes that is between the price range of $55-$75 (depends on the shoe).
I am starting to design a few myself. I am going to start off simple.
I made Buzz Lightyear sneakers for when I dressed up at Buzz for Mickey's Not So Scary Halloween Party and they were my first pair that I ever painted.