In Australia, there are government subsidies for sugar production.
Hence junk food with craploads of sugar in it is really cheap in Australia.
I've recently switched to a low sugar diet (actually it is a variation on calorie counting), and it has roughly tripled my food budget.
Also, the 'Health Foods' section of the supermarket contains some of the most expensive and bad for you food in the whole place. All the fat is removed, and replaced by sugar... but they slap a 'Healthy' label on it and sell it for twice as much. So you end up with a tiny muesli bar which isn't particularly filling, and contains as much calories as a normal meal.
I can give suggestions if you want (so far I've lost 11 pounds).
Or you could google 'The Hackers Diet' by the guy at fourmilab I think.
Note: some of the stuff I eat isn't traditionally viewed as healthy food - I can eat a chocolate bar for instance. But I just have to find a way to fit it into the calorie budget. Also, to count calories I will go for the known quantity every time. Eg a known quantity of Coco Pops is better than an unknown quantity of Sultana Bran. Instead of milk on my cereal I just use a small potle of yoghurt. The milk might (or might not)* be theoretically better than the yoghurt, but the yoghurt is a known quantity of calories. For the same reason, I'm happy to grab a six inch (or even two) from Subway after going to the gym.
*After I started looking on the calories associated with various foods I realised that in a lot of cases there is stuff all difference between the calories in say chocolate flavoured milk and ultra reduced fat 'skinny' milk. Likewise, many boring cereals that advertise as 'healthy' have more calories than their delicious and 'funner' equivalents.
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