Do not wear sunshades inside your house or in an enclosed building.
Sunglasses are meant to protect your eyes from the sun. Some are photochromatic while others are tinted just for the sole reason of protecting your eyes inside the sun. It is really improper to wear them inside your house. It is wrong. That is why it is called a sunshade, not a room shade.
One of the properties of fashion is that it is functional, and the use of clothes generally emanated from this property – to cover our nakedness. Just as our dresses our functional, some of our accessories are also functional. Go for the fashion ones instead, if you are really a shade freak.