Company branding is an important aspect of PDF creation that many tools struggle to handle correctly. PDF documents often need to include logos, company colors, fonts, and other branding elements. Puppeteer is popular because you can control these aspects through CSS. However, Puppeteer can be challenging to work with for larger documents, as each change requires programming effort or when your software needs to needs to serve multiple clients each with different requirements.
Yep, it's mostly about branding and control. It needs certain concrete layout and logos, and has to be relatively easy to change them.
We also render shipping labels in PDF, and we have to be VERY strict with that. But we're still not touching that, as that process is not at slow and problematic as the invoicing one.