Perhaps it’s a political statement?
Seems unlikely from the PGA TOUR, but NBA players famously wore hoodies in protest a few years ago, and England’s football team has been dealing with fallout over racist posts on social media this past week.
Personally, I think golfers (like everyone else) should wear whatever makes them comfortable, and anybody who doesn’t like it should mind their own business, but you all know what a bomb-throwing radical I am.