Then look at it another way, why should the US military fund the personal needs for cosmetic surgery? You tiptoed past that by pointing out how small the outlay would be compared to the size of the DoD budget and that the US taxpayer pays a greater amount for the Pfizer riser.
Whataboutery is a stylistic type of argument that has its place, but somewhere along the lines, your argument has to stand on its own merit. Your argument pointing out that the Government spends millions on Viagra only tells me that we're wasting money there as well.