I don't think that's a valid statement. There is only so much 'stuff' that you can use. Beyond a certain level more money does not translate into a better quality of life or more 'stuff' for most people, there are a few outliers but lots of very wealthy people are actually quite modest. They're so modest you won't read about them in the newspapers.
I don't think GP is saying that the demand you add to the economy increases linearly with income. I think the point is that it's essential to have lots of people with a healthy amount of discretionary income, because non-discretionary income can't really be reallocated no matter how compelling your wares are.
Yea, it's more important because there are more (or should be more in this era) people in that range as a percentage of population than strikingly wealthy people.
I don't think that's a valid statement. There is only so much 'stuff' that you can use. Beyond a certain level more money does not translate into a better quality of life or more 'stuff' for most people, there are a few outliers but lots of very wealthy people are actually quite modest. They're so modest you won't read about them in the newspapers.