My school's water is undrinkable to to high lead levels so they bring in bottled water. They run out way more often that I'd like so I always bring my own water. Now it's a habit.

Weird I haven’t noticed this when traveling. I don’t carry a water bottle with me in Europe. It’s in my carry-on for the plane but once I leave the airport I don’t take it with me on daily excursions. Maybe because they took it on the flight, they just continue to carry it?

What's wrong with having water while you are out and about?