Spelunking vs. Caving

So a while ago, a friend of mine and I went caving, and while driving to our destination, I was informed that caving was the prefered term rather than spelunking. When I told him that caving was too monotonously regular for my taste, he said that many cavers will become offensive about the term used. Personally, you could add "ing" to almost anything and make it an action, where spelunk is not only an origional word to use, but is rather fun to say as well. So take that cavers, I'm a spelunker. What I would like to know, is why caving is the prefered word to those in which this applies. Any takers?
Yes. I'm in a cave here.