What's always surprised me is how cheap ophthalmic surgery is. I don't think opthalmic surgeons are exactly slumming it, but the cost of say getting a cataract removed is under $4k per eye with no insurance.
Some of the reasons might be that the procedure is fairly quick, the eye is easy to get to, it doesn't require general anesthesia, and doesn't require a full OR in a hospital (I think - correct me if I'm wrong). In that sense its closer to oral surgery than a gall bladder removal, for example.