Expenditure cascades is an economic term coined by researcher Robert H. Frank. It describes changes in purchasing and consumption behaviour which ripple through the levels of income in response to changes in income inequality.
Example
During the late 1900s and early 2000s, income inequality in the United States rose dramatically, and expenditure cascades occurred. During the 1980s, the income-tax structure was altered to favor top earners in regards to after-tax purchasing power.
References
Expenditure cascades Wikipedia(Text) CC BY-SA