Yep. And I suspect that in places where they get hundreds, thousands of chicks at a time (*) they aren't using a heat lamp brooder as we small fry would think of it. They likely use huddle boxes. Basically a big MHP or EcoGlow type thing except they are using light bulbs for heat in that space.
And like MHP, they go in and out as they please to warm up. They aren't in a "95F the first week" red lighted ambient space 24x7. Sadly, when I Googled "Huddle box for chickens" I came across a LOT of home red heat lamp brooders and some software.Think of it like a large wooden box, suspended from the ceiling with an open space all around at the bottom.![]()
* My wife is a PO clerk, there is a meat chicken farm up the road, they get 1,000 chicks in a single shipment.
That has to be LOUD! I know when I go to the PO to pick up my order of 10-20 chicks I can hear them from the front door!