Those are some interesting points to mull over. The rapid wear does make sense, but remember that the majority of people who perform these modifications are doing either for drift style racing or the look of a drift car. I had a set of stretched tires on my truck, albeit not low pro tires, and had no issue telling if they were under inflated. I also got 45,000 miles out of the set. The truck had an incredibly tight limited slip and ate through tires like crazy anyway. Also take a careful look at a Le Mans modern race car. They keep a little more meat on the wheels, but still have the rim either even with the edge of the tire or slightly stretched. Again think about the fact that these, like all other modifications, can be done right or wrong. I agree that 18 sets of tires is excessive and am trying to figure out why they would get ate up so fast.
Some people are ignorant enough to blame their bad driving habits on tire manufacturers. Also bear in mind that the super low pro tires, 30 series (sidewall height) and less, are not load rated or rated for speed at turns. These tires are produced for style, not performance. Performance tires are 35 series or higher.