Someone asked in a report "How often is there more than one in a town?"
Not too often, but where I live in Berlin, we have 5 Esperanto clubs. :)
Why is it "de" rather than "da"? The "klubo" consists of "esperantistoj," right?
True, but we are not concerned with quantity here, as we would be if we used "da"
Are you saying that anyone who speaks Esperanto must be a nerd? That sounds like a sweeping generalisation to me.