I think it has to do with [derogatory term I'm sure will be deleted] knowing a song because of some popular show/movie, only because of said show/movie without knowing a single thing about the band..
In some weird way, it's cheapening and even demoralizing.. It can also tarnish your view of said band in the age of prominent sell outs..
And before someone questions 'sell out' (because someone always does) so many bands/musicians now are completely changing who they are, and what music they produce, just because of the customer base.. IMO, when you start making music just for money, you've become a sell out.. Sure, lots of people, even good bands, want to make money.. But when you just start catering to the masses, you've sold out. An artist should be expected to receive compensation for their work, they should not expect to be paid for 'creating'.