Cars have very low profit margins. Last time I checked a few years ago, the gross margin on an average American car was 10-15%. This doesn't count finacing.

That is a good reason, but in and of itself, not a sufficient reason.

Chocolate has fantastic profit margins. No Apple chocolate. ... mhhhmm, apple chocolate, that sounds yummy.

A bit closer to home, fabbing microchips has great profit margins. Apple pays good money to TSMC.

Just because it's good money isn't enough reason, I am sorry.