If you have a pair of shoes that leaves your feet aching every time you wear them or, worse yet, actually damages them with blisters and contortions, get rid of those evil bastards.
There are sexy shoes that don't cause agony. Really.
There is another new pair out there that can make you as happy as those worn out ones that can't live up to their former glory (or arch support) anymore.
Take care of your feet; they work hard for you.