I can't speak for fabric shoes, I usually buy leather. The way to expand a leather shoe that is tight, like a ladies heel, is to put them on with a thick pair of socks, then hold your blow dryer over them until you get the desired fit that you want. It doesn't take long. Be careful and keep checking on them, you don't want to expand them too far too fast. This works very nicely for me and ladies high heels that might be tight in the toe box or around the rim or heel.
HTH