If your society has an agrarian model, where you locally produce, distribute, and serve all the food you need to subsist, and these chains are small-scale and numerous, then there is more trust inherent in that model, and less pressure for profit or growth. Therefore, many of the motives are removed for adulteration or poor-quality food. These can be relatively self-regulating industries as described.

In an industrial, developed first-world country, you have massive factory farms scaling up, you have ginormous distribution networks on rail, water, tarmac, and asphalt, and they all run with help from the massive oil industry, and finally you have large-scale food service operations and restaurant chains and mega-groceries all over town. So yeah! There's gonna be a lot of motive to mess with food, and there's gonna be a lack of trust in the Big City, because these supply chains are so long and deep, spanning oceans and borders, that it's very impersonal. So those are ripe conditions for adulteration, reductions in quality, false labeling, and all those things the FDA/USDA/FTC have striven to eliminate on the behalf of the consumer, I guess.