Carly Rae Jepsen's "Call Me Maybe" is one of those songs that tricks you. You only have to hear it once to know all the words. Not just the chorus, ALL OF THE WORDS. Who knows where you even heard it the first time?
The problem is you will hear it again, and inadvertently signal to your peers -- fellow full-grown adults -- that you like the song. They will think you like it because you are singing along word-for-word, despite only having heard it once. When the chorus hits that weird interval at " ... this is crazy," you will realize you hate this song. You will stop singing, but the damage is already done.
Somewhat related: It's not that crazy to give out your phone number, though I am worried Ms. Jespen has been a little too sheltered.