Hi there, I posted this email response from MPC in a couple of places on the forum. But none is a dedicated "Where do the MPC chicks come from" post so it's kind of buried.
So here it goes: We're not a drop ship service, exactly. We do work with a hatchery, but use our own incubator space, employ our own chick sexers (for instance, My Pet Chicken is the only place in the country that sexes bantams), have our own breeds and so on. For non-live items, we have our own My Pet Chicken warehouse and supplies, but do have others fulfill sometimes, depending on the item--some of our coops come directly from the manufacturer or builders, for example.
I'm glad you posted this question. I have emailed them for further clarification.