Keep in mind the revenue protection problem was not just to/from gatwick, but people making other journeys and stopping off at LGW mid journey.

As for trolleys, they have been allowed on the transit for years and years. While I can vaguely remember a time there were not, I'm wondering it that was a different airport, as I can also clearly remover "trolleys are allowed on the transit, please hold the brake firmly during the journey" since the first days of the north terminal...