My mistake about the AFA/LWB, though Synth Foods undercutting the AFA prices amounts to pretty much the same thing as taking their jobs. They can claim that they dislike Synth Foods because of the corrupting outsider influence, but the loss of business probably has at least as much to do with it.
The Gaians are so fanatical (at least, the Gaians who are more than just pirates) that they violently object to terraforming lifeless balls of rock into habitable planets. How could they not object to the ecological destruction caused by wide-scale farming?