Might be true sometimes, but you can still get better shots. Your camera in #1 and #3 is metering and exposing for the brighter background and making your subject's faces too dark. Using fill flash would not be too hard even for candid shots and would definitely help you get better light on their faces. Also, even candid shots will benefit if you compose your shots without your subjects placed close to the middle of the frame when shooting with a landscape orientation. You seem to be really good at capturing great expressions.