Quote Originally Posted by Bourne_Endeavor View Post
Extra retainers simply allow for easier omnicrafting or storage.
In practice this is far from the case, ventures have proven to be a very lucrative market allowing players to amass astounding ammounts of gil in a short period of time due to the extra services they receive with multiple retainers.

Retainers make earning gil easier than without them, it can be construed as paying real money for more spending power ingame.