The Boots theory is funny because it's absurd. It's not actually applicable to life in powerty. There is no class of items where if you are poor you spend more on it than when you're wealthy. People in poverty spend more _time_ on things, yeah, but not more money or money per use.
You can see some discussion on that from people who actually grew up poor in https://mastodon.social/@danluu/111068036776213383