I think the prevalence of socks with sandals has scared people off of wearing socks with heels. I'm not talking about regular socks though. Think socks like the ones shown above.
Lace socks, beautiful glittery mesh socks, pristine thigh high socks and if you're feeling quirky, textured socks with kooky designs.
As long as they're not average bag socks with huge logos, they can look great with the right shoes. If you're starting out, remember things like the complimentary color wheel, or look up cool artist color palettes on Pinterest or Tumblr.
If you don't know what I'm talking about, artists across social media platforms will give themselves challenges, like creating a drawing with specific palettes they generate themselves. A palette made out of varying shades of muted pink and purple, for example. They can be a great guide when it comes to socks and sandals, which both cover an area that usually isn't given as much thought as the rest of the outfit in casual fashion.