When Sarah sings Time After Time in S02E12

I've only watched the DVD versions of the first 3 seasons - and there is a scene in the 12th episode of season 2 (Hold On Tight) where Sarah and Bailey are in a store and she sings Time After Time by Cyndi Lauper - but the song isn't playing in the store - it just seems random - so i am just wondering whether it was supposed to be playing in the background prompting her to sing it but due to copyright it was removed from the DVD or it was like that when it aired

It just seems so random