May 17, 2013 No Comments FREE Nature Valley Granola Bar at Xtra Mart Print out the coupon and redeem for a FREE Nature Valley Granola Bar at Xtra Mart. Available at participating Xtra Mart locations. Valid 5/17/13 – 5/30/13. Locations. FREE Nature Valley Granola Bar at Xtra Mart – EXPIRED Facebook Twitter Add Comment Notify me of follow-up comments by email. Notify me of new posts by email.