> Stores higher more employees for the holiday shopping season and then when the season is over, you reduce headcount back to normal.

They do. The difference is that the additional employees stores hire for busy season know that they're being hired on a temporary basis.

> "hire people when you need them and fire them when you don't" isn't evil or incompetent.

It is if you weren't clear to the hires about the expected lifespan of their position.