It would be far less costly if the vitamins were made of chrystalized synthetic vitamins, rather than food derived. Chrystalized synthetic ('USP') vitamins give you exactly what you pay for, no more, no less. They are cheap, which is why everybody uses them.
Absolute levels of vitamin C are not the best gauge of efficacy. There are several studies (remarkably unnoticed) in the literature which show that no amount of synthetic ascorbic acid will reverse scurvy symptoms, whereas vitamin C from biological sources such as acerola or lemon will in extremely small doses. The starting point for synthesizing ascorbate is corn dextrose, and UPS ascorbate can have in it upwards of 10-20% unreduced corn sugar. Biogrown nutrient vitamins are typically lower in dosage, but because they are generated out of a microbial life process feature as well the enzymatic intermediaries that were keyed to their production, such as lipoic acid, ubiquinone, quercetin and the maleates. When a multivitamin in crafted out of USP synthetics, you get only pyridoxal hydrochloride, thiamine hydrochloride, riboflavin hydrochloride etc.
By the way, I disagree with you regarding the use of ascorbate to bowel tolerance for flu symptoms. Evidence suggests that this purgative effect (in addition to the infectious process itself) renders the intestinal lining hyperpermeable to gut bacteria. There is also the phenomena (at least in certain Eastern Europeans) of 'rebound scurvy', where large amounts of ascorbate generate increased capillary fragility. Pauling, as you may know, received his Nobel Prize for determining the 'pleated sheet structure' of certain proteins (the result of his work in X-ray chrystallography) not for his later advocacy of high dose ascorbate, which in recent work seems to incite chromosomal abnormalities, at least in cell culture. As my father used to say, 'Sometimes too much good is no good.'
I could also add to the discussion the health benefits of the cultured food part of the formulas, but your question addressed only the vitamins.
BTW, I pulled your post entitled 'Give the Diet the Heave Ho' since that is a priori always an option, and I felt the title was disrespectful of my work.