There is also an inductor and a 1500uf cap rated at 6.3V. Wonder if they are generating Vin for the Nano. The Nano also is different. It has 12 & 16 MHz crystals on the back side.Strange behavior for Eleks adding anything. Did they double the price?
Yes, they generate +5V on board using a DC to DC converter to supply power to Nano +5V pin (disabled by default - there is a solder jumper near inductor). I wrote more about this here:
My guess is that they will use this board for more than just laser engraver. They probably have more designs in the works for a mill or drill table etc so they are supporting these design with same board. In the scheme of things, the cost increase will be negligible but the flexibility it offers returns value for them.