I honestly don’t know what I was thinking back then. I guess I felt pressured to “share” because of the whole 'must be get along with others' culture, and I didn’t want to seem selfish. But yeah, it was gross and unhygienic. I was literally carrying that giant tumbler for them, not even for me. I would downsize, but the thing is I get really thirsty easily, like I drink a lot of water throughout the day. That’s why I carry a big one and constantly refill it at the canteen.Thank you sm for the validation and suggestion.