[quantdev]

I don't think the hedonic treadmill or that link has anything to do with your statement "the average person spends almost exactly as they make as income rises." The hedonic treadmill says that happiness is eventually independent of income and savings. So, eventually, whether someone makes $1mm/year, saves none of it, makes $1mm/year, saves $500k, or makes $30k/year, saves none of it, s/he'll have the same happiness.

Also, your statement is false. The average higher-income person saves both more money on an absolute basis ($ amount) and on a percent-of-his/her-income basis.