You're assuming that every purse is the same and that women all just toss it in and don't take care of their cellphone. I'd venture to say my phone in my purse is more babied than people's phone in their pocket. I make sure it's not moving around (my purse is tight and things have to go in a certain way). It gets cushioned by my checkbook on one side and a spare maxi pad on the other. And I try to make sure nothing else is next to it. And it's pretty solid in there, I don't believe in big purses, blech. And if I had a big purse it would have to have a cellphone pocket that would keep my phone from moving around and other objects from moving around and hitting it. And I'd probably still want some padding (I do tend to drop my purse so that is exactly why I pad the iphone in my purse).
It's so well cushioned that my iphone 5 survived my motorcycle wreck without a scratch (the paramedics were amused I was asking if it was ok). That happened the same week I got my iphone 5 (I got it launch day) and it still works perfectly fine now (it has a scratch on the front but it wasn't from that but from dropping off my nightstand and getting wedged between the nightstand and the bed <- my nightstand is an old PC and the cover on the side near the bed isn't on it so there is a little space for things to fall between).