Excellent points!
When I was a super-dub I remember having conversations with different ones that would last several minutes. But, they were always about non-spiritual matters. It does seem that it's easier to talk about restaurants, sports, music and other generic stuff than to discuss anything scriptural.
Now that I'm fading I have a really hard time discussing those generic things because I'm no longer in the JW mindset, I'm bound to slip up and say I like something evil or saw an evil movie. - just like FairMind said, you're going to talk about what interests you and if you're out/on the way out you will screw up sometime.
Can you imagine having a deep scriptural discussion with someone like we sometimes have here. Take the Headcovering thread for example, there is some really deep thought on that thread, but you'd never have that kind of disucssion at the hall. The discussion would start and stop at, well the bible says to wear a headcovering. OK goodnight.