If you snag them the day they hatch - you can take them and raise them.
But then you don't learn about incubating and don't have an incubator and if disaster ever strikes, and it does with some frequency - you won't be ready. You'll have to come here in a panic and read it all, learn it all and buy or make the incubator in a day.
I hatched with broodies. Then broodies made mistakes, or got snagged by predators and voila eggs and no parent, or damaged eggs needing careful handling.
Having an incubator and knowing how saves a world of grief, panic and remorse when you need one immediately. While I have broodies - there is always one incubator running in my house. If something happens, I have a place to immediately move a damaged but viable egg, an injured hatchling or an orphaned group of eggs.
I hatch in a homemade. I had an LG - one of the little foam ones and learned to work it, but didn't like the design. Because better ones than the LG cost more, I built one. Then learning from that went on to build another. The current one is Darthbator, a black mini-fridge bator. It's delightful. I got the non-working mini-fridge free off freecycle. I had the parts from the previous bator and from recycling the fridges fans.
Cheap to make, easy to use, works like a charm. And is there if I need it. I hatched out about 80 chicks and poults in it this spring.
Knowing HOW, having what you need available for an emergency... priceless.