TheSundayHerald.com By Barry Didcock WE MAY be in a recession but nobody seems to have told the select band of pop stars and rock icons currently filling the world’s stadiums and concert halls. Perhaps that’s to be expected. What’s less understandable is why their many millions of fans are also ignoring the economic facts and paying three- four- or even five-figure sums for tickets to see their idols. Whether it’s Bruce Springsteen, Madonna, Prince, Leonard Cohen or Tom Waits, it seems o