why is there a package.json export for `package.json`?

Hi,

Apologies if this is the wrong place to ask but I wonder if it would be possible to explain why `package.json` is included in the exports?  

```json
{
  "exports": {
    ".": "./dist/index.js",
    "./*": "./dist/components/*/index.js",
    "./styles": "./dist/styles/index.css",
    "./styles/*": "./dist/styles/*/index.css",
    "./package.json": "./package.json"
  },
}
```