Thread sealant can be used for a variety of reasons....usually to counter warranty(loose barrel), provide a secondary lock (torque + thread lock), water intrusion blocker, tamper resistance, or to mask an improper joint. I'm guessing it is the last one since the thread diameters are so large and the nut is so small that it probably doesn't properly friction lock with the applied torque. Add to that it is loaded cyclically and failure causes a total loss of use....this is likey why they use thread locker.
Without testing, I have no way of knowing if needed, but I thing know is the generally accepted answer.
A light oil combined with a torque intended for light oil is the way to go. Check torque after 10 rounds and make your call from there.