Lots of people thru hiking in the Smokies plan to arrive late, so that shelters will be full, in which case it is (in normal times) allowed to hang yer hammock outside the shelter. Now, it doesn't matter, 'cause I heard that they boarded them up.
Below quote from
here...
Shelter and Privy Advisory
Many A.T. shelters and privies are closed due to the difficulty of social distancing and the possibility of COVID-19 being transmitted on surfaces. Whether officially open or closed, hikers are advised to avoid shelters and picnic tables, and bring their own personal shelter and food storage device.