But.. but but but... does it matter, if you're going home or
going out to meet friends after work? If you carry a bag everyday,
it wouldn't be obvious where you're headed after work, would it?

Mmmmm I love carrying home-made drinks like what you had around. It
just feels very nice and comfortable to have such things, when
everyone else is either having coffee, plain water, tea or other
instant stuff.
I used to carry ginseng tea to school during examinations. In a
thermos flask.