(Note: posted by Mike Saunders from The Document Foundation. I’m adding this as a link on Frequently Asked Questions | LibreOffice - Free Office Suite - Based on OpenOffice - Compatible with Microsoft so that people can discuss here further, if necessary, like with the other questions on that page. Thanks!)
Mike, I would add a note on Frequently Asked Questions | LibreOffice - Free Office Suite - Based on OpenOffice - Compatible with Microsoft to the effect that TDF does not charge for any available download of LO products.
In addition, there’s now a version offered under official license from TDF also for the Windows Store: https://www.microsoft.com/p/libreoffice-vanilla/9npr3bznj4dm
Likely not. LibreOffice is free and open source software and can be redistributed by other people, subject to the license. But if you want the official version from The Document Foundation, you should always download it from our website. Note that some of our Certified Developers provide their own versions of LibreOffice with long-term support options.