I do, JTB. It's an interesting phenomenon. I don't know if they register and lurk and get scared away or what. Perhaps they are just very shy. Or on the trip planning boards they could be finding their answers without asking.
A very small percentage of DISers visit the Community Board, I think. I remember when I registered I stayed on the planning boards until I had all the answers I needed. That took about 3 weeks. I can remember I logged on and I had no questions to ask, I hadn't had my trip yet, so I sure didn't feel comfortable answering other questions but I was hooked on DIS. I didn't want to give it up. I found the community board then by scrolling through all of the different boards under the "just for fun" category. I never left the planning boards before that.
Great question, JTB. It is interesting to think of reasons why people register and never post.