Whenever the issue of opening the RAF Club to non-officers (or similar debates about messes on stations), there is always the assumption from some that the system is some obsolete classist conspiracy by officers to keep 'them' out. It wrongly assumes JRs, SNCOs and WOs would like nothing more than to spend their social time with officers if only we would let them... Which is clearly not true.
I had a great bunch of people (with the odd exception) in all the jobs I did as a JO flight commander. Sometimes, we also had some good nights out as a flight... But not every Friday. My JRs would have had no desire to hang out with the boss all the time and vice-versa. It's nice for everyone to get away from the structured heirachies of the day job and relax. Ironically perhaps, the mess system allows that (sort of).
Applying the same principle to a London club, one of my corporals on a romantic weekend with his wife does not wish to stay somewhere where he might see me and a load of other JOs smashed at a sqn reunion... And vice-versa.