It's a cultural perception issue, mainly.
In the west, when we see plastic, we think of litter. And we should, because there's way too many coffee cups, cigarette butts, and fast food wrappers lying on the ground in our towns and cities.
But in Japan people don't litter. So when they see plastic, it's associated with clean new products. The trash still ends up in the ocean, but they don't see it happen - out of sight out of mind.
The amount of overpackaging in that country is absolutely insane. But counterintuitively, they're going to have a hard time getting rid of it. Here, there's a decent amount of public consent for paper straws, biodegradable packaging materials, etc, thanks to the cultural guilt we have because we're surrounded by litter. Over there, people "do their part" by simply not littering - but that's not good enough.