Michael Bennett’s Feb. 11 letter (“Medici Would Be Skeptical on Student Loans”) refers to the return on investment on the GI Bill versus the student-loan program. The GI Bill was a cost-of-living stipend, plus free tuition. This, I submit, forced everyone—colleges, students, book publishers and landlords—to keep their prices in line because they knew to a penny how much (or how little) their buyers could afford.

Similarly, when I first started traveling for work in 1971 my per diem was $30, later raised to $36. That had to...