For the record I am neither Chinese nor Asian, but I assume this is just active voice for dramatic effect.

This isn’t some novel phenomenon special to Japan. Seasonal local festivals that attract many times the local population happen everywhere. At first there’s trash everywhere and general chaos.

Local government and event organizers adapt and improve infrastructure. Or they throw up their hands and say the tourists are impossible to manage.

In the modern day, they monitor social media and predict crowd sizes based on impressions and engagement. They respond with increased infrastructure that includes trash and bathrooms. That’s actuarials.

Common sense is that tourists don’t shit in yards without extreme circumstances forced upon them.