I'm lazy and taking caps on and off is too much work for me.
I use clear lens caps on all my lenses. B+W UV MRC. Not to protect the lenses, although they might, but so I can leave the caps at home and also not worry about keeping the lens glass clean.
I'm not a real photographer but I occasionally take real pictures.
I use the XS timbuk2 snoop - very stealthy
I keep putting in the wrong name. It's Jin Mao Tower
Jin Bao Tower