I would suggest a ban on selling alcohol in glass. But I think a ban on glass stubbies would do it. Put beers, RTDs and other stuff that currently comes in stubbies in either aluminum cans, or plastic bottles.
So you can still have wine and spirits in glass. There's a whole lot less of them, and they're a small fraction of the smashed glass pollution problem. They're almost never the ones I find smashed on streets, in green belts, or at festival sites.
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Coming back to Castle St though, back in the Cretaceous I lived there for a few months (long story). When I lived in Ōtepoti again in the 2010s, I walked through there a lot.
I've seen the mountains of glass, and the remains of the odd burning couch. But I've also seen vacuum cleaners being passed around from flat to flat. There's an incredible sense of community, even though almost nobody lives there for more than a few years.
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