Field displays different value for different users

For one user, the Assigned To field in my Case detail view shows the full name, but for every other user it shows just the user’s username. The only customization on that field is readonly=true. They are both using the same view and viewdef. How could this be?

I am running 7.11.3

That’s actually an option in the User profile!

User Profile
Show Full Names

Well that explains it! Good to know I’m not going insane. Thank you.