Susan Boyle was dubbed 'the Hairy Angel' after her revelatory performance on Britain's Got Talent. But Tesco's own-label NuBo, Irish checkout crooner Mary Byrne, has become the subject of complaints over less- than-angelic behaviour.

Retail rivals were carping this week that producers of the karaoke sideshow were name-dropping Tesco at every opportunity. Poor Mary couldn't get a mention without awestruck references to the fact she has a real job. Even the judges were at it, seemingly fixated on her supermarket status despite their famed flair for relating to mere mortals.

Clearly, the barrage of name-dropping has nothing to do with Tesco being the only place selling X Magazine, which targets the minority of X Factor fans who can actually read.

After the Auto-Tune fiasco, one contestant emerging as a human Dustbuster and another facing deportation, you wonder how long Tesco will want its name linked with the increasingly shabby circus. Still, that didn't stop its commissars emailing 300,000 staff to remind them of the show.

"We are fully supportive of Mary and so are her friends and colleagues at Tesco, but as to how anyone votes, that is up to them," said a spokesman. That's that settled, then.