Some random questions, as I didn't want to start a new topic for each of these.

I want to start collecting Aqua Pura and know I can take them all at the Citadel and Jefferson. But even though

it is not considered stealing or causes karma loss, it still feels like stealing. How do you RP/justify taking the
Aqua Pura?

Is there a list of where the random encounter with the wasteland who has a wasteland survival guide can occur?
Same with the scavenger selling a Quantum?

Do merchants who sell misc stuff also sell Nuka trucks? Or is it just the ones you can find in the wild?

Thanks in advance