All of the above.

I may buy a Gatorade or ten, but I don't think I've ever paid for water on a trip. I usually stay in campgrounds with potable water supply. That gets me started in the morning. Whenever I stop, I usually ask if I can fill my water bottles. I've never been turned down.

If I was getting low and needed to fill up at a house, I'd knock on the door and ask. It would be a hard person that wouldn't allow me to take a couple of bottles of water from their outdoor faucet.