As a user I don't want any of my data going to third parties at all.
As a website owner trying to provide a service to my users I want the best experience for them. This might be linking to third party services that are doing a better job than I could.
I only see this going one way. The user will have to agree to the sharing of their data with third parties if they want to view third party content, or want the fonts rendered in a better was. Link NPRs text version when you don't agree.