How plausible is it to believe that the businesses which feed into counterproductive activities are likely to be much more profitable?

If we go with the very pretty Austrian theory that profits tend to be equal across all parts of the economy (unusually high profits draw capital in, unusually low profits drive it out), then the conspicuous profits in fashion-driven industry are counterbalanced by lower odds of making those profits.

I don't know how good the empirical evidence for the Austrian theory is.