Not only is it ridiculous, Mike, but it is putting staff at greater risk for no reason other than FOBT-driven greed. Who is likely to come into a betting shop at that time of night, if not those who have either just left the pub and are therefore a bit more argumentative, or those looking for trouble?
And let’s not forget that one of the three licensing objectives of the Gambling Act 2005 is "protecting children and other vulnerable persons from being harmed or exploited by gambling." People under the influence of alcohol and/or drugs are classified as "vulnerable persons"; if the majority of people stumbling into betting shops late are night are either drunk or stoned (or both), surely the bookmakers are directly breaking one of the licensing objectives?