Magazines are owned by publishers and publishers like to make money. The way to do it? Make sure the magazine appeals to the most amount of people as possible. Who are those people? Those that happen to like the biggest bands and want to read about them/learn their songs. AND those bands happen to be - you guessed it, not black/thrash/doom/viking metal ones.
Guitar One has it's moments - they actually teach you something - but GP is the only one that's really focused on playing and not writing about this month's Emo stars...
Although GW *does* have a nice Heaven & Hell article this month.
What that ad meant by EXCLUSEVILEY is that, My Chemical Romance plays only SIT strings, not that they are the only band using SIT strings, retard (thread starter)