For the same reason why people don't use scheme: they don't understand it, so they don't bother with it. I know scheme myself, and I don't bother with it, as I'

For the same reason why people don't use scheme: they don't understand it, so they don't bother with it. I know scheme myself, and I don't bother with it, as I've not had the time to really learn the libraries that come with plt.