Knitted material that doesn't develop little furry balls (pilling)
Pilling occurs when shorter fibers work their way out of a yarn and gather on the surface of the fabric. Generally, pilling occurs due to a given fiber's length/strength, the spin/ply rate of the yarn, and the surface abrasion the garment is subjected to.

As to the hat you're posting about, all layers and lining are composed of synthetic fibers. As such, they are extruded and artificially cut to lengths for processing; longer lengths are generally chosen, though this is not always the case. The yarn itself is also quite finely spun, so any given fiber will span multiple wraps over its length, helping secure it in place.

Also, synthetics tend to be fairly strong for their weight, especially olefin and nylon, and will resist breaking. When other fibers break, the resulting pieces of the broken fiber are then short enough to easily work their way out of the yarn.

As a hat, abrasion is probably pretty low. I do have a knitted hat that I occasionally wear under my bike helmet, and the added friction has caused the hat to pill considerably, when normally hats don't do that as much.

It's probably also worth noting that this hat has multiple layers. As such, abrasion to the inner surface of the hat will have little impact on the outer surface, and vice versa.