Final answer:
The changes in family structure disrupt the traditional family life-cycle pattern of consumer spending, contributing to income inequality across households in recent decades.
Step-by-step explanation:
The changes in family structure, including the growth of single-parent families and two-career high-earner couples, disrupt the traditional family life-cycle pattern of consumer spending. These changes have contributed to income inequality across households in recent decades. Single-parent families tend to have lower incomes, while two-career high-earner couples have higher incomes. This uneven distribution of income affects consumer spending patterns within the family life-cycle.