that's a touch plate switch, so the lamp contains a hidden black box with a microcontroller that sits in a tight loop waiting to detect your finger
Project 62 Valencia lamp wasting 2.5 watts.
at least the circuit board that connects live AC to a metal plate on an ungrounded frame does have decent isolation :P
http://joeyh.name/blog/entry/Project_62_Valencia_Floor_Lamp_review/