I have to say that this needs to be treated like Driving.
Agreed, CT.
Firstly, I enjoy a drink as much as anyone else and from time to time a good session.
But many of us in the UK see the apathy and complacency with which drink driving often gets treated and not just by the public but also publicans.
How often do we see the same cars in the pub car parks for hours on end whilst the drivers sit at the bar getting slowly loaded. I'm not saying it doesn't happen but I can honestly say I have never heard a landlord refuse to serve someone they know is over the limit and who they know will drive home. I am afraid their ostrich-like attitude may bite them in the posterior severely one day.
I know there are those who will argue that it is not the landlord's responsibility to police the drink-driving laws but surely they should be taking some responsibility in the (potential) chain of events.
I do feel the people at the sharp end need to be a bit more pro-active.
And this should include the CFI at your club. I'm assuming he/she is included in the people who know of the problem.
Talk to a lawyer about the potential problems your club could face if something went pear-shaped - that should make them sit up and take notice - not to mention the damage to GA from the tabloid headline 'Student Pilot Killed By Drunk Instructor'.