As a rule, metal will always dwell in the underground. This isn't to say metal bands can't headline arenas or don't deserve major awards, only that the genre is one that will always reject mainstream appeal due to the price of compromise that usually comes with it. Metal fans will often secretly envy pop acts for always landing the Super Bowl Halftime Show, and adore heavy acts that lean towards the theatrical and easy-to-love side of things (looking at you, BABYMETAL), but deep down most metalheads know that this sort of broad appeal would water down their favorite genre. Just as Groucho Marx would never want to be part of a club that would have him as a member, so too would fans be bummed if an Obituary were used in a Pepsi commercial.
What's especially interesting is when this goes in the other direction. While pop stars seem to reject metal in their sounds and sensibilities, there's a long tradition of mainstream artists using parts of metal's image and culture for their own devices. And while the most typical example of this is the appropriation of merch and style – the fashionable vintage concert shirt, the logo done in kuh-razy black metal font – it occasionally goes deeper, illustrating a deep-set appreciation for the genre's core power and meaning.
Here are 10 times that big non-metal acts have decided to take a stab at the left-hand path…