I wear sunglasses inside stores and outside any time the sun is up because it allows me to walk with my head up. With out the shades, my head suddenly drops, and I'm looking at the floor trying to hide my eyes from the light. From a couple of human relation college classes I had, a head down is perceived as low self esteem. From the junior high (middle school) bullies, I learned that walking with your head down makes you a target for bullies.
Another reason I wear sunglasses as much as I do is to reduce my anxiety. I can't tell when I'm anxious, so instead I look for the opposite, relaxed. I don't feel relaxed with my eyes squinted so I wear shades to relax my eyes.
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I finally found an avatar.