Actors cost at least £2 more an hour than ride staff...
Terry only has about, 2/3 actual actors right? Hell the ones who let you off the lifts are probably used in the actual corridor itself, saves money (and lots of people in one area)... I guess Sanctuary might have at least double that, and as mentioned, the other costs such as lighting and other effects will make a difference... But the main cost is definitely the actors...
In addition, what with the low attendance so far, one could say it's the extra fat being trimmed off as well to save some money... And as I said, they need to have the Towers opened up as an agreement with the council, hence it was never going to be permanent...
I really couldn't care less mind... Never interested me...