it looks to me like the brakes might actually still work. Looks like it's mounted to a spike in front that at my guess goes through into the snow as a brake...
yeah you're right. i thought about that too but i don't think that there is a spike or something that goes through his front ski(even if this would be cool). maybe he just didn't want to unmount them because it feels more natural if you still can put your index finger on the lever.