I know some climbers that have been climbing for quite a few years, and while I do not know how their feet were before they started climbing, I can say that their toes do have a shape resembling that of a climbing shoe. Mainly, the toenails have a curve to them, and their toes are sort of squished together.
Though, this doesn't mean it's necessarily because of the climbing shoes. I know people who have similar feet/toes that do not climb, and I also know climbers whose feet have not changed, so it's hard to say for sure if climbing shoes change the shape of your feet or toes.
I have been climbing for a few years now, and my toes seem to be more curved now than they used to be. The tips of my toes used to all be round, now they are sort of "pinched" in the corners.
