Economists do not all think that way. Just as there are many differing perspectives in other sciences (feel free to cringe if you are a mathematician, chemist, etc.), there are a range of schools in economics as well. Though I cannot fully delve into the topic at this time, variance is certainly taken into consideration by many economists. Depending on the situation, (number of betting cycles etc.) variance is very important. So, in a one-off bet, it makes sense that the utility between these choices would differ.

I tried to find a good resource that further explains this but wasn't able to quickly find one. If I am able, I will try and post one later today.

On a final note, all of the situations in this quiz are easily correctly answered (or in some cases, predicted) with a basic knowledge of statistics and economics.