Quite simple really Max, why stand around for half an hour whilst your ferret try's to move a stubborn bunny from a blockend which could be shifted from a 2 minute dig?
Why stand around waiting whilst a ferret is laid up on a kill, or leaving a kill behind and finally emerging, which could be dug out easily? (what was the point in ferreting in the first place if your leaving kills below ground for no reason.)
Why stand around waiting when there could be 3 or 4 rabbits up a tube that could be dug out easy?
Why set 20 nets when a big hob could pin a rabbit in seconds and dug to in mi