Whenever I've "had" to wear one, I've written messages on them, like, "THIS MASK IS BROKEN/DO NOT USE."
I also have one where I drew the mural image from the movie Scarface.
People like it.
People of the Chinese persuasion wear them in airports forever. So what? Their air is so crappy they’re used to it! You can wear a gas mask riding your bike for all I care!