It really just depends what they're feeding the cells. Not many people are interested in eating a lot of buckwheat and sorghum despite their nutritional value. But plenty will eat meat. Thats the benefit, you can feed the cells very cheap, hopefully space efficient crops. Crops that taste like ass to humans. You can cycle those crops out to avoid soil depletion and monocultures too, which you can't do with something people like to eat like potatoes or carrots as easily.

I wouldn't say its a very good comparison to compare them with cars.