I get the feeling he doesn't like the shadows in the game. Just a hunch.
I suspect he had to make this video in his car because if he did it at home his mother (Probably still lives in the basement) would make him turn it off. Something like this:
Mother (yelling from another room) "Who are you talking to down there?"
Tool (yelling back up at his mom) "Nothig mum!"
Mother "Well I could have sworn I heard voices. Come on, who you taking too? Is it a girl?"
Tool. "Nobody mum. I'm making a video!"
Mother "Oh a video. Not another one of those disgusting videos your pop and I found in your dresser drawer. The one with you all.."
Tool "NO MUM! Nothing like that! I told you to stay outta my stuff!"
Mother "Well what are you going on about down there? You're making an awful lot of noise. Its distracting me from the telly"
Tool "I'm talking about the shadows in GT5 mum, now lemme be!!"
Mom "Oh Jesus Mary and Joseph, not the bloody shadows again!"
Tool "Shut up mother!!"
Mom "Day and night, on and on about the shadows!"