I wear sandals when it's the summer, and I'm not at work. I don't give a shit how they look, it's a comfort thing. I don't do the cell phone clip thing though, for a few reasons. I do think it looks dumb, but it's also inconvenient for me, as I'm fat, and sit down a lot at work. So, if I had a holster, it would be constantly digging into the side of my gut, which is not a good look, or comfortable.
I've never EVER understood sandals and socks though. That seems like covering your convertible with a tarp.