As a piper, I have a couple of pair of white hose that I wear for competition, even as a soloist. They are not required of competitive pipers, but over the years I have perceived a prejudice by some judges (not all) against soloists versus individual pipe band members. So, the white hose are a part of my disguise. I don't care for white hose for (semi-)formal wear because it makes me feel like I'm wearing white socks with a dark suit. I don't like off-white hose because it makes me think they need a good washing. So, I pay the money and wear colored, diced, or argyll hose. BTW, I attribute winning one bonniest knees contest to having worn a pair of black-and-red hose.