I think they're worried about legal procedings, both from Shebang's camp (after all they supposedly put him through rigorous psychological testing, to ascertain that he was suitable for the BB experience
), and from the person who might be expected to take the blame for Shebang's inclusion.
I think he was an attention-seeker, rather than a genuinely troubled individual, but once he started going on about wanting to die in the house, they would have had to pull the plug on him (no pun intended!).
They can't show smoking during the day time, as it might incite young impressionables to take up the habit. Ditto suicide threats, perhaps.
