The issue there and most likely the reason they said no/nothing at first is they simply can't answer "no, I don't want anything, just give me cash!!!". They have no problem acquiring chocolate although to be fair, it may not be free for them and it may not be a specific brand they want
With sleep vs going to shore, they have a system in place where one person picks up items for everyone else. In some ports, you can have things affordably delivered to the terminal. On most cruise lines including X, not only is there no free-wifi, they cannot buy unlimited wi-fi. So even though they're tired, if the terminal area or a crew spot has relatively good free wi-fi, they'll most likely want to get off to check on things back home with wifi that's faster than on the ship