Dang! That kid was born to play hockey! as far as the reason he's the only one on the ice. I think it's kind of like a "Foul" shot maybe?? I don't watch hockey either...
During intermission for both home and away games, they bring local youth hockey players ontot the ice and do a 5 shot 1 on 1 shoot out. they start with 12 boys teams and 12 girls teams and as the year goes on, they narrow it down to a winner for both boy and girl.
I remember watching that shot, it was during a bruins away game in toronto (why all the seats are empty) They only show the shoot outs on the NESN, the local sports network.