That was my thought as well - but on the flip side, by dealing in quantity they are a lot more likely to have one leak and be reverse engineered, and thus have Apple render them all useless.
It's certainly an interesting problem of profit maximization!
Unless the vulnerability is in the CPU/DMA/whatever and not easily patched. Everyone assumes that Apple has no idea what it is, maybe they are keenly aware and it’s just not fixable.
It's certainly an interesting problem of profit maximization!