When Tim McGraw agreed to perform a benefit concert for Sandy Hook Promise, a non-profit organization that seeks to prevent gun violence and is led by family members affected by the tragic Sandy Hook school shooting, he certainly didn’t imagine the controversy it would cause. Opener Billy Currington dropped out after conservative website Breitbart.com posted a story titled “Country Singers Tim McGraw, Billy Currington Headlining Gun Control Fundraiser,” but Little Big Town are defending the show and its headlining act.