This is basically true, but the amount of taxpayer money is usually, well, infinitesimal. Reason: These cases often occur in studies which aren't very popular or occupy intense lab capacities, will say, it simply doesn't matter, whether there are 30 or 32 students in the lecture about Relevance of Salon de Refusés for the early impressionism. In crowded or care intensive studies, they will probably fail to pass the exams. So this taxpayer argument is a typical American one and often simply doesn't apply. At least those suggested extra costs should be proven before claimed. It's a political argument, not an economic one. If all, then laboratory equipment and salaries are affected, not the number of enrolled students.