18 pages still going strong, huh? If we're actually talking about "metal" bands and not AC/DC or Guns N Roses (both of whom still probably wouldn't win...), there is one answer:
- Metallica can sell out football stadiums and giant arenas with no opening band, and force their fans to endure Jim Breuer yelling "YEAH" into a microphone for an hour.
- Metallica are the only band (not just metal) that have performed on all 7 continents (and they did that all in the same year).
- Metallica can play The Grammys, perform with Lady Gaga, have terrible sound issues, and still be viewed favorably by fans.
- Metallica can release an album in any year and it will be the top-selling metal album that year.