Why else would he pepper spray himself?
I have to save myself from myself.
The best part of the story is it sounds like the pepper spray was given to him by a fan. Whether is was or not, I think that'd be a pretty good gift from a fangirl. It's like a warning that "Hey, you might need this to protect yourself from me when I start stalking you." That's thoughtful.
Other thoughtful fangirl gift ideas:
"Hey, here's a paper shredder for when I send you my fanfics and pictures of myself."
"Here's some earplugs for when I scream things outside your home at night."
"Here's some hand sanitizer for when I throw my panties onstage."
"Here's this shank in case I make it past security. Luv U"