Is that a donator perk?
Nope, any time a sentry or dispenser is built by anyone it will have a random hat from a preset list on top.
Also, Punishment, not sure why I didn't notice this till now, but those texture resolutions are seriously low. I honestly thought you had put a mosaic censor over the text on the dispenser for some reason, then I looked again and realized that all of the textures are blurry in your screen shots.