Cokeheads No Longer Allowed in Clubs

For reasons that we cannot fathom, bouncers and cops in the UK are now using a device to ensure that people who sniff coke don't get into nightclubs. What?

Some misguided individual has invented a UV flashlight that reveals all the little tiny bits of cocaine on your face. Cops are using it to destroy the nightlife business:

COCAINE-using clubbers were refused entry to a Blackburn nightclub after a high-tech ‘magic torch' device revealed they had been sniffing the drug...
Four men were stopped from entering Liquid and Envy nightclub in the town centre on Friday night.

Where are cokeheads welcome, if not at "Liquid and Envy"?
[Animal NY. Pic via]