... There are different materials that the body is made out of.
Different coating that make the body more scratch resistant. Paint -> HA-II ->HA-III etc.
This always annoys me, I don't know why. There is no such thing as HA-II. HA stands for Hard Anodizing which is Type-III anodizing. Type-II is not HA. HA is much tougher then Type-II but Type-II is much easier to color and create.
Back to the original question.
Cree is an LED manufacturer, Their XR-E LEDs have many different bins. P3, P4, Q2, Q3, Q4, Q5, in order of efficiency and brightness. The cheaper lights might use the lower Bins and the more expensive ones might use higher bins.
There is quality cost, machining cost, labor cost, shipping cost, and few others. There is also R&D cost, since some cheaper lights copy from the more expensive companies. All these add up to a big difference in pricing.