Northern Light
Superstar
I don't really get the point... is it a stunt?
Yes. (it is a stunt)
Though, I would suppose (speculation) that the idea is : (beyond getting people vaccinated in general)
a) To make it seem exciting to get vaccinated to motivate a few people who are reticent.
b) To brand Toronto as a safe place to visit for business or tourism which is likely to re-start in earnest in the not-too-distant future.