Just as an update---man it's been a while--
But earlier this year I finally found Blue Moon shoved on the bottom shelf in Sainsbury's in the American Beer section (lot's of Bud, Coors Light). Sold in individual bottles for I believe it's 1.69 at the moment, but every so often there's a 3-for-2 on. They also have Brooklyn Brewery which is quite tasty--I remember selling it at the Staten Island Yankees when it was first brewed!
Needless to say, I clear the shelf when I see it and also informed the manager that as long as they keep stocking it, I'll keep buying it.