I bought a pair of flip flops once to wear around the house, I had always despised them but, wanted to give them another chance. I threw them out two days later.
I'm still trying to figure out why people wear them outdoors let alone wear them at all. Feet are the foundation of your body and very valuable. Don't disrespect them by letting them get all filthy and unsupported by a lousy thing made of some weird foam and plastic.