I know my employer is selling my data to all kinds of third parties. Microsoft is collecting my info through my required use of Outlook and Windows. Confluence has my data. Salesforce has my data. My company even uses linkedin for certain trainings which means they are getting some of my data. I've explicitly avoided some of these companies because I didn't want them to have my information, but my work insists of handing out my data like candy, often before I'm made aware and can even object to it.

My company isn't even always paid directly for it, but it's factored into the costs of the software and services they pay third parties to provide. Many businesses are willing to give my company a deal in order to make sure that employee data gets into their hands/databases.