The flaw in this analysis is that you think chipotle only sells salads. They obviously don't. At least based off my experience most people order burritos/bowls, not salads.

Here's my analysis: per wikipedia, chipotle has revenue of $5.586 billion in 2019. If we divide CEO's salary by that, we arrive at 0.68 cents per dollar of revenue. According to wikipedia, chipotle doesn't franchise, so we can assume that's all food revenue. Assuming a salad that costs $10, that's 6.8 cents of CEO comp per salad sold.

The calculation is then:

Compensation / (daily consumers * days) = average cost added per person fed (and, if once per day, per item sold).

This allows us to ignore the price per item or total revenue, which might be misleading.