That’s interesting.
Can’t say the group you mention in Britain applies to Australia. We haven’t done a full study in Australia about affected, specific demographics. Not that I’m aware of so far. A full study is can be expensive too. Though reasons I mentioned before are key ones in Australia, and pretty much apply overall.
True. The junk-food factor is pretty much reflective of the underclass (or college students), while the other items you mention are more of the "good intentions but poor application" sort.
Australia introduced Vegemite to overcome Vitamin B deficiencies. Maybe the government should start a program to promote the use of Emergen-C. One packet a day would boost everyone right up.