The story about the diet soda...
People that do not drink diet soda on a regular basis generally do not like diet soda and think it tastes funny, so it would be reasonable to assume that the pleasure from the sweetness would be differently displayed.
I wonder what the results would be for long time heavy drinkers of diet sodas, that prefers the artificial sweetners and actually think real sugar tastes awful (yes, we do exist). Would sugar light up the same parts of the brain as it would in normal people? Would it light up the parts of the brain associated with bad tastes or unpleasurable experiences?
About the grasshoppers' terror...
Sounds like a survival thing, beneficial to the grasshoppers. If there are predators present, it's not a good environment for survival. By causing less vegetation to grow, they make it an even less hospitable environment for their species, driving them to find greener pastures where there would be not only more vegetation, but less predators, as well.
The study on the success of movies based on advertising costs...
The first rule of advertising states:
He who has a thing to sell
who goes and whispers in a well
Is not apt to get the dollars
as he who climbs the hill and hollers.
It would be reasonable to assume that if he can afford a megaphone, he'll sell even more...and if he can hire more people with megaphones to climb up on other hills, even more.
We could probably repeat the study with similar results here in the US, but based on politicians and the money raised and spent to finance their campaigns, and the election results that follow. This is what all the noise over corporations being able to funnel unlimited amounts of money into campaign funds is all about, essentially allowing corporations to buy elections. The politician with the largest purse, generally wins, and corporations are in a better position to finance political campaigns than private citizens are, very much the same way the big movie studios can buy more viewers than a small indy company can, based solely on the cash available to spend on advertising.
About the milk fats...
There is a good reason why lactose intolerance in most species of adult mammals is the norm.