Mystery Jets grounded

Is it just us, or does US immigration seem to be applying the letter of the law a lot more closely for band visa applications these days? The latest of a flurry of bands forced to cancel American dates is the Mystery Jets; apparently Canadians Handsome Furs have also been told they ain't coming across no border - although, of course, they could just sneak across if they were that bothered. What with there not being a big fence at the northern border.