I never really viewed it that way personally. I think the Junimos are very carefree, happy spirits. You build a hut for them, you don't buy them, so this means they move in on their own. You don't tell them to harvest crops, they just see full crops and decide to do it themselves. They like to harvest crops and they keep them in their hut, and they don't mind that you take them because they are technically yours. They enjoy and react to things you leave them too, including their favorite snacks. I think it's more of a symbiotic relationship, especially after they willingly moved out of their homes in the community center. They're happy that you provided homes for them on your farm too so they like to help you. I think it's very sweet and cute.
Also, not to mention, you don't even need to put them around crops. They're just chilling and doing whatever. I've never, when I've had huts, viewed myself as owning junimos or making them work in any capacity. But, that's just how I view it, and I don't think it conflicts with the game's messages in the slightest