[1rudeboy]

Because you are smug, regardless of how wrong you are. So let's review.

For the purpose of calculating the CPI, the BLS:

1. Includes food and energy,
2. Accounts for shrinking packaging sizes, and
3. Does not substitute chicken for beef.

[xzins]

Because you are only partially on the right track:

Core Inflation does not use volatile food and energy

The CPI does have a substitution function in their formula.

A market basket of goods is weighted based on purchasing habits. Those habits cause updates every few years.