For me, it's not about price. It's about necessity, quality, and usefulness. Like, I have my Wet N Wild 666 lip liner. It's 99 cents and always has been. I started using it when I was in high school, and it's great.
Coming out of college with a degree in fine arts and painting isn't worth much any more.
Another cause of change, one less noticeable but fundamental, is the modern growth of population closely connected with scientific and medical discoveries. It is interesting that the United Nations has set up a special Commission to study this question.

