If GaryH is saying its incredibly busy today, I cant see what makes you think its pointless and that there would be no one there? + if its a nice evening I always think people are more inclined to stay. I always think this hence why I harp on about crappy opening/closing times over the summer period. If its a gorgeous evening people aren't going to go "blimey look at the time, nearly time for bed." at 16:00pm 17:00pm whatever. Its more to do with Towers just wanting to usher the paying guests out.