First you believe in yourself and you stand up for your shoes that you like. For example, if they starting dating the sneakers are not”cool” you can say maybe to you but not to me. In a more directed way you could say “focus on your own shoes don’t judge mine.” Or if you want to be super direct “Who asked your opinion?”
C. The main reason they use actors in Media is because in our society we find it more appealing then if the product was just to be shown to us.