Re: What they do
Purchase close source projects and change the license to open source. Create the own open source projects. Maintain open source projects with a professional level of quality assurance. Distribute open source software in accordance with the licenses. Offer subscription based customer support.
They do not take software from multiple sources with different copyright owners and licenses, remove the attribution and licenses, chew what is left together and sell the result as if it were not the creation of others and mostly likely stand back and laugh when the recipients get into legal trouble for distributing the resulting code.