How would you possibly monitor this?
As awful as it sounds, truth is the police will just laugh you off.
If you go to a club, you're almost guaranteed (male or female) to have someone touch you in a way you don't appreciate. I probably find just as many drunken girls will grope my bum/boobs in a club as men do!
People just sort of assume it's accepted.
Obviously there's a big difference between someone groping you once or twice, you telling them to leave off and them dancing off into the distance, compared to, someone groping you and then pursuing the situation by
following you into the toilets... It's like fights in clubs, the police really aren't bothered. I've seen so many people drunk outside clubs, having been barred because they 'got in a fight' and the police have been called, they will simply tell you to "Go home, sober up and just try not to get so drunk and argumentative next time to prevent this happening again."
The police don't want to be taking statements, taking drunk teenagers home/to the station (likely to throw up on the car seats) etc.
If people decided to report to the police every time they were inappropriately touched in a club, the police would be doing nothing other than arresting drunken teenage girls and boys.
They would then need larger police forces to tackle the other issues, which would then end up coming out of our pockets and then we'd have a thread saying...
"Why do people report every tiny incident that occurs in a club?!"