I said high-end. Look, say, at 2014. Apple was buying 4770HQs while the businesses would have been using i5-4300Us. The only Windows machines with 4xxxHQs would have been very high-end mobile workstations or gaming laptops, neither one of which are huge volume sellers.
Also, Apple used almost no i3s, while HP/Dell/Lenovo have sold plenty of i3s over the years.
I don't know about the server chips, the Xeon Platinums and the like and what volume those sell in, but there are a lot of high-end laptop chips that Apple used, especially in the 15" models.
I guess maybe another way of putting it is - I'm sure Intel's margin on the chips it sold to Apple was much higher than on what they sold to Dell/HP/Lenovo for non-server products. That 4770HQ doesn't cost a ton more to manufacture than an i3-4010U, but even at whatever discounts Apple probably got, I'm sure it sells for a huge amount more than the i3.