Does anyone know why the gunge hashtag on Instagram is full of pics of the Foo Fighters? Specifically Dave Grohl and Taylor Hawkins?

It seems really weird to me. Like I get they can be considered part of the Grunge music subgenre of alternative rock, I can see somebody misspelling the word when they try to add #grunge to their post but if that was the case I'd expect pictures of Nirvana, Pearl Jam, Alice in Chains, Mudhoney... etc. Why is it only the Foo Fighters??

All from different accounts as well. There must be something among fans, some in-joke maybe(?) that is causing them to upload pics of Dave, Taylor, the full band and tagging them #gunge.

I don't even mind the band, it's just driving me a bit mad. Anyone know the deal? Of course when you Google all results are essentially "did you mean Foo Fighters GRUNGE??" - no Google, no I fucking did not.

Could be a joke they have been known to do many such jokes in times of tragedy
https://youtu.be/lLlKZcqLK7k
I also could be mistaken and Twitter may be having a spell check error