if you hold the chicken while the box is being moved out and then let go after the ''ka-ching'' then it won't teleport back, probably figured that out already but I just want to be helpful :)
here is how to keep rare chickens but sell their boxes.
step 1: take the chicken out of its box and let it walk around
step 2: put the chicken in the incubator
Voila! you can now sell your box!
