I'm from California, and people here love love love to wear flip flops all the time. I used to wear them everyday, but they also wreaked havoc on my heels too! I always slather on lotion on my feet after I take a shower and put on socks. They make my feet baby soft and super smooth. But wearing flip flops every single day will still dry out your heels no matter what.
As a result, I've stopped wearing flip flops everyday. I wear them occasionally during the summer, but I wear ballet flats, heels, sandals, and other types of shoes now. Five years later, now I hate wearing flip flops. I guess I've just become accustomed to NOT wearing flip flops now.
Also for the past 8-9 years, right after I take a shower I apply lotion and then put on socks. I swear by my handbag obsession, I have the softest, smoothest, most glowing feet ever!
A couple weeks ago, my mom was peeling the dry skin off her feet and complaining that it hurt and she wished her heels weren't so dry. So I showed her my heels, and she exclaimed, "Wow, it's like touching a baby's butt!"