I'm guessing it's meant to be a way to obtain Mega Moglification without having to get a Stall made through synergy. One piece of guild furniture gives Moghancement, two pieces gives Moglification, and 3 pieces gives Mega Moglification. According to ffxiclopedia, just having the Stall by itself will give Mega Moglification without the other pieces of guild furniture. I installed my Stalls without pulling the other guild furniture out, so I can't say for sure.
Lyonheart of Lakshmi
lvl 99 NIN WAR BST THF BLM SCH WHM
1/467 on signed HQ Weskit!!!