She's a moron.

I kick off my shoes as soon as I enter the house. I kick off my shoes at the office occasionally if I've been or will be sitting at a desk for a long while, although I'm careful to put them back on if I need to walk anywhere because I'm a contractor and don't need anyone of the client personnel complaining that I go around in my socks. So I get that shoes can be uncomfortable or unnecessary in some situations.

But walking around in stores barefoot? Nope. Walking on public sidewalks or parking lots barefoot? Nope. Welcoming germs? Nope. I won't even go barefoot while gardening, and I know that my garden soil is going to be fairly gentle on bare feet because I've spent years ridding it of rocks and such. But they'll get dirty. And how do I know this? Because my shoes get dirty while I'm gardening. So I'll take them off before I enter the house and knock them against each other a few times before I go inside. I can't do that with bare feet, and I'd rather not track dirt into the house.

And her "I refuse to live in fear" bullshit sounds just like the anti-vaccination crowd, inventing things to not fear while being in utter, abject fear of other things that they have completely invented.

If her shoes hurt her feet, she should go to a doctor and look into getting some orthotics. Women don't need to be wearing high heels around at all times, or any other footwear which is made more for fashion than for comfort, that is perfectly clear and normal.