If Apple wanted to bin the chips, they have devices crying out for low-power draw, albiet slower clock. They can sell a tonne of earphones, watches, HDMI enabled USB-C dongles. They could re-purpose chips which can clock 10x slower for 1/2 the cores, and still have too much CPU. But free.
They can use them for the Apple touchpad, the keyboard, the on-mobo controllers which currently consume non-general-purpose chips, if they want to. If they displace a 10c part by an otherwise redundant $30 part, they are still ahead, if it works.