Understanding Class Usage in Style Guide Headings

I have a question re: classes in the style guide. heading-style-h1, heading-style-h2, etc. How come the styles aren’t just applied to the ‘All H1 Headings’, ‘All H2 Headings’, etc to limit the amount of styling used on pages? I understand the classes come in handy when you need a H1 applied to a H3 size for SEO purposes, but seems like when sites are imported from Relume, every single header has a class applied to it. Just trying to get my head around the reason for it