Thank you both for the detailed explanations. It makes sense considering it like this, but...
I'll admit that I didn't even think about chicks being shipped directly home ! This just doesn't exist here (and although it's been thoughtfully discussed before on this thread and others, I still strongly disagree with it).
I was thinking mostly about buying chicks from big stores like TSC. Wouldn't that cancel all the sanitary precautions that could have been taken by the hatcheries ? Here, when AI was a concern one of the thing people were told was to avoid AG stores or take complete biosecurity measures coming home. It seems like the perfect place for a virus to spread.
I did a five weeks quarantine when I bought the four POL pullets but honestly it would not have been effective if there had been a viral disease. I don't see how it's possible to do a proper quarantine free-ranging, and I don't have it in me to lock up chickens in my barn or second chicken shed for five weeks. Even if I had, dander could still have flown through.
As for the price, I think it's not such a good reason because chicks are so much more fragile. Initial cost may be cheap, but add starter food for several months without getting eggs, and the fact that you are not sure they will all survive... and it seems as reasonable economically to pay for an adult pullet that's about to lay.
I don't have butts for tax from today, because it's so hot all the chickens are hiding in deep shade

This is Théo's butt from a few days ago.
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