Interestingly enough, this isn't entirely true.
While I've abstracted it a bit for this quest, a farmhand would not be expected to do things like pile manure or things like that. He gets paid a wage and even that can be an insult depending on the job that is done.
A farmhand has higher standing than a shepherd (who is someone who receives only room and board, not wages like a farmhand). The shepherd would pile the manure, the farmhand wouldn't. And, if there were thralls, the thralls would (generally) be doing the less desirable tasks.
It was straight up illegal to assign farmhands demeaning jobs like watching the sheep.
Now, obviously this is a bit different for the Quest (because I forgot, lmao) but yeah.
Still, the basic logic applies.
If you somehow get a robot strawman on your farm who will perform basic manual labor, you assign the strawman to the second-lowest position on the farm occupied by humanoids (above whichever thrall pissed you off that week, but below all the other thralls). The strawman now does thrall-work, which frees up thrall-hours to do more thrall-work, which means the dividing line between "this shit is thrall-work" and "this is farmhand-work" can slide slightly upwards and the farmhands concentrate on doing
more of those high-prestige tasks so that the farm as a whole accomplishes more.
It's complicated, but it's basically just "managing everyone's hours, Norse edition" with extra paranormal crap.
...
The hell kind of thing is it that Horse and Sword is more valuable than Ship and Sail?
Unless we're talking about some wild ass shit in both events.
Maybe it's a matter of degree. Or that if you're very rich and high-status and expect someone to go on a quest for you, you're expected to pony up something more valuable than an actual pony. Because going "I will pay you, hero, to perform this noble quest" while keeping your orthstirr implies that this is a problem you
could totally sort out by headbutting it personally but have some valid reason not to go for, and you (being a badass) regret not having the opportunity to deal with it yourself.
The wealth you have to sacrifice to adequately convey how much it sucks that you're not able to go personally suplex that zombie elephant and are instead hiring another badass to do it for you... probably scales somewhat with just how rich you, yourself, are. And just how high your reputation is for performing other related tasks such as suplexing gorillas, rhinoceroses, and sharks.