Nope.
I don't think just because ducklings -- or chicks are "livestock" animals they deserve any less consideration than any other animal.
And I completely understand that other people have "pets" that need to eat, too -- my son recently lost his beloved lizard that required living crickets or dubia roaches. Still, the crickets or roaches that I used for his pet were kept in a clean and lovely environment by me until such time that they were used. I didn't write off their existence since they were "feeders" -- I didn't buy "pets" -- I didn't seek out animals that were wild, or that someone had raised for other purposes.
I am also not a vegetarian or vegan -- I have been all over the world, and am culturally sensitive having had close relationships with friends and colleagues who eat things that a lot of my American friends would find distasteful. I have eaten, or at least tried things that I wouldn't share with friends and family here at home because they'd not understand --or at least be judgmental.
That said, like yourself, I would NOT sell or give my ducklings to people in this situation. I did not give my pullets in a similar situation. It's the same with kittens or puppies -- I wouldn't give them to someone wanting to use them as food for a snake or if I knew the home wasn't safe, etc.
