The Mo Dong Sect had a very wise policy of requiring its guests to leave their weaponry in the custody of Mo Dong Sect personnel for safe keeping during their visits. That way, if any of these guests had actually come to Mt. Mo Dong looking for trouble (as was often the case), he/she/they would have no weaponry advantage over the Mo Dong Sect members. It's the kind of security provision we see in many public places today.
But it seemed that Mo Dong Sect was the only sect that practiced such a safety measure. All the other sects didn't seem to ask their guests to surrender their weapons before entering the hosts' grounds. Why did this security measure seem unique to the Mo Dong Sect?