I arrived to find that a) everybody except me seemed to know each other, and b) everybody except me had brought a bottle of wine. Fortunately b) helped me cope with a), and I felt qualified to voice my opinion. I could even get a word in edgeways, so considerate was the company.
A couple of those present had worked in the Civil Service, and several were old enough to recollect the era of the novel, so the discussion was interesting and soon veered on to social mores of the 1960s and when exactly flavoured crisps began to appear ("Smokey bacon is a very 80s flavour"). Lots of hands went up when we were asked who had actually visited the Atomium, and I shared my story of checking out the exhibition about the 1958 World's Fair with the book fresh in my mind.
I'll definitely go along again, though only if I've read the book in question. Next up is Station Eleven by Emily St. John Mandel, of which I know nothing.