you have to understand too especially on the Loverboy clip NO ONE knew if this guy could sing or not...when he starts chanting "hey hey hey" at the beginning of the song

watch the look on everyone ELSE'S face on stage...they are ready for a train wreck.

just to be clear this guy was just pulled from the crowd when Mike fell ill...and they sort of half heartedly asked if anyone could sing.  his friend was pointing at him
and they brought him up./