I am one of those people who loves to joke around and tease. I sometimes get myself into trouble because other people take things more seriously. I suspect that some of the posts referred to by Stephen, but definately not all, are really only meant in good fun. Some of the giffin grip jibs, for instance. At any rate, "in good fun" is the way I choose to interpret most of it.
On the other hand, maybe the old german saying applies: "In jedem Witz liegt ein graenchen Wahrheit." In every joke there is a grain of truth.