If a gas can in scavenge ends up somewhere unreachable, shoot it, since it respawns after a while. This happens surprisingly often with exploding boomers.
God exists if you want him to. Your reception of reality is an illusion, it's impossible to be objective. If you see God, he exists. If you don't, he doesn't. It's not unusual to be spiritual. It's a completely normal and understandable human desire. However, view the universe objectively, and...
I think my favorite is becoming The Parish, it just seems a lot more replayable than the other campaigns (especially Hard Rain becomes meh, due to playing the same levels over and over and over).