Yes, not a surprise but here are some details:
We identify a strong negative relationship between the consumption rate and the lifetime net resource. The predicted APC [average propensity to consume] of the highest net resource cohort about 0.03, which is two standard deviations smaller than the lowest resource cohort.
That is from a new paper by Ilin, Ye, and Yu (Yu is on the job market). Of course this relates to the recent wealth tax debate — almost all of that tax would fall on the investment of the wealthy, not their consumption. Note, however, that if the wealth tax induced more consumption by the wealthy, consumption inequality could quite easily go up.