It is correct to say "It don't"?

I was listening a song, "I and Love and You" by The Avett Brothers. At the begining of the song, they say:

 

One foot in and one foot back
But <em>it don't</em> pay, to live like that
So I cut the ties and I jumped the tracks
For never to return

 

Can somebody clarify my doubt?

 

Thanks.

 

"I and Love and You" by The Avett Brothers: http://www.youtube.com/watch?v=Fv0R5R3TSmw