I have noticed a big difference. My chicks that arrived from a hatchery were neurotic! Screamed when I picked them up and were always afraid of my hands. The ones I got from a local breeder were the most tame, sweetest birds.
No surprise here, when you learn about what the newborns went through getting the poo squeezed out, thrown into baskets, held by the head to get shots and swung inside a box during shipment as a "welcome into the world" ritual! Add to that never knowing the security of mama's warmth under her wings...
I can get part of what you observe purely by how I access the brooder. When I tower over bitties and visit infrequently they are flighty. When I access from side, visit frequently, and move very slowly and offer live food they must appraoch me for they are much tamer.
