Source from
where? It's easy to apply your mental model of a supermarket to the supply chain... oh, chicken isn't available? We'll just go get some beef.
That's not how it works at global scale. If chicken isn't available, there isn't necessarily anything else to pick up the slack. There certainly won't be if other supply chains break too because we neglect them all, one-by-one, thinking something else can just pick up the slack.
Food is a necessity. It's arguably the only necessity being truly threatened by our reaction. It means that, if necessary, the "adjustment" that should be made is that people may be pressed into work by government force if necessary to keep it flowing. Anybody who is necessary, not just "plant workers". (Most likely starting with the National Guard and the military, if necessary.)
Food supply chain breakdowns are not an inconvenience. They are an existential threat, and csense is completely correct; it is 100% a greater existential threat than the pandemic, if it gets going. In fact, the pandemic isn't even an existential threat on the same scale; the absolute worst case possibilities anyone ever posited for the coronavirus are still childs play next to civilization-scale food shortage.
Now, I do not personally have a good bead on how big this threat is right now. There's a world of difference between Farmer Bob had to dump a few thousand gallons of milk and saw a chance to turn it into a photo op and/or blame some other problem he had on the coronavirus, and entire months' worth of production going down the drain across the industry. I do not have a good bead on whether this is a drummed-up talking point or a legit crisis. However, it is important that we find out for real, because if there is a real problem here, it can rapidly dwarf the coronavirus itself.