Exalted with Tillers - Question on Farm hands helping

So I'm exalted with Tillers, all 16 soil plots are unlocked, and I have Yoon as a voted-in member of the union (completed that quest chain).  After all this, there is a quest at the Sunsong shrine that asks you to become best friends with a Tiller, and have them join you on the farm.  I'm BFF with every Tiller and apparently you can only have 1 Tiller at your ranch at a time. 

The question I have is: what the hell do they do?!  I can't discern what each Tiller does because I can't discern any difference on my farm regardless of who is there "helping"!  I've had Haohan there for about two days now and he has produced nothing.  Is this a bug, some kind of strange companionship vanity, or am I missing something?  I'm very curious. 

I invited Jogu, just so its less of a walk to get to him and ask which plants are going to give more loot.  Gina is the only other NPC that can provide being usefull, just to repair quicker.  I never had to repair there after being done with the Tillers by hitting Exalted, so I've preferred asking Jogu. 

For the rest, they do nothing.  But now I never have to leave my farm to go to the market atleast.  Such a small perk for so much work

I really hope there would be some bonuses from having a farm hand, ie.  Sho really keeping pests away etc.  Few times i had 7 pests simultaneously on my crops.  And those fucking wild tentacles!  I just HATE every button-smashing events and your Gnaw's cd is lower than their Slam sometimes...

Gotta wonder why you can't have multiple farmhands that are actually useful.  Granted getting to exalted isn't tough, nor does it take an exceptional amount of time, but I expected them to do SOMETHING.