The labour is relative, for my current set up it takes me less than 5 minutes a day to care for them.
I feed them once a day, and every 7 days they get cut. The reason I expressed that a shallow tray is important in to make life easier, every time I frag the aips I just use a curved long scissors (the same scissors used to cut grass on planted tanks) and in a similar way it only takes seconds to go around and cut the aips on the stem near the foot without getting my hands wet. There is a lot of chemicals released during fragging attention to use protective equipment is always required.
For feeding I use one of these hatchers
It doesn’t take long to set it up. Obviously on a larger scale it would become more of a job as any other breeding process.
Nudibranch will eat any sized aip, they can eat very large aiptasias.