This is the official reason:

https://www.foxnews.com/entertainment/the-weeknd-explains-full-face-bandages-super-bowl-halftime-show

Now, I'm probably 100% completely dead wrong about this, but...

There have been hints/rumors that certain people might not be at "room temperature" like we've always been led to believe. Should this be the case, then how would one go about "resurrecting" such a person to the world? What if you wanted to go for maximum effect? How would you do it?

Well, if I wanted to be dramatic -- after all this is a movie -- I'd stage a performance --- like, say, at the Super Bowl where everyone would be watching --- and have a performer wearing bandages all over his face. At some point during the performance, when people are caught up in all of the special effects going on, I'd switch out the performer with the person in question, then at the end of the performance, I'd have them rip off the bandages and make the big reveal. Live. On national television.

Wouldn't that be the most jaw-dropping, shocking thing you've ever seen??