By all accounts, this year's Fuji Rock Festival was a success. Punters of all ages and demographics enjoyed the laid-back vibe at the three-day music spectacular — give or take the constant rain — and most social media posts about the event focused on good times. Not everyone was happy, though.

Dig a little deeper and another particularly vocal crowd emerges. On the official Japanese-language Fuji Rock blog, several posts featured photos of the grounds covered in trash, one featuring a photo of a garbage-coated table was simply titled "How does this make you feel?" Similar sentiments appeared on social media, with users posting shots of abandoned cans and others trying to assess blame (soft verdict: probably young people, possibly foreigners).

Garbage and the failure of some to clean it up has become a recurring issue among Japanese netizens. The annual Sumida River fireworks took place the same weekend as Fuji Rock, and Twitter users circulated pictures of "mountains of garbage." Many online expressed shock at the lack of morals from those in attendance who saw it as OK to just leave their litter in the street.