Although I agree it's what's inside that counts most, I think that people try to put what's inside on the outside. The way a person chooses to present themselves to the world does say something about them.
Having said that, I'd never be shallow enough to go by that alone. I always get to know someone before I make any final decisions about them.
I honestly don't even care what shoes a guy wears. If he wears expensive shoes, he probably just think he looks cool in them. You can't read a person's soul just by their shoes. That's rude and its what is on the inside that counts.