Ireland do them as well,since Walkers started selling in Ireland we got Ready Salted(about 30 years).I seem to remember a crisp discussion recently and you mentioned green,red and blue bags and some companies did it differently to their competitors,watched this last week and it was very entertaining/informative;They don't. The Chinese shops sell all different sized packets. The wee souvenir shops and supermarkets just sell the big bag though. Lays do a rather nice salt and vinegar. UK must be one of only a few countries that eat salt and vinegar crisps.
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https://www.channel4.com/programmes/the-secret-world-of/on-demand/71484-002
and a couple for @EasterRoad1980
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I'd recommend them all
