I thought they were slaughtering animals without benefit because they lacked the labor to slaughter them for retail sale. Iff that's the case, panic buying helps them not at all and maybe makes the PR side of things even worse.
Panic buying also fails to help them if they basically can't raise prices to take advantage of it. It's not like panic buying is going to line their pockets, and certainly nowhere near enough to compensate for the damages they seem to be suffering.
Frankly, if doing that's not the primary point of the ad I don't know what is, since it's going to be the main thing it's sure to accomplish. If they don't want panic buying and shortages they must have had a hell of a good reason to for-sure cause them in service of maybe achieving some other effect.
Panic buying should be one of the main concerns here. The average American who is able to maintain several weeks worth of food supplies between grocery store should be trying to go to the grocery store as little as possible during this time with a reasonable expectation that there will be food there when they go. If panic buying and shortages start occurring, these same people may feel compelled to visit the grocery store increasingly often in hopes of finding the food they want or need. This could increase transmission rates a non-trivial amount since going to the grocery store is one of activities most likely to put us in contact with a contagious person in our everyday life.