Bohemians live in alternative spaces, these are places that are not normally considered suitable for living in. They don't make wealth their priority. Money is only a means of survival, so they can live for their arts/craft/music/literature...etc.
What causes ice-ages? Fluctuations in the amount of insolation (incoming solar radiation) are the most likely cause of large-scale changes in Earth's climate during the Quaternary. In other words, variations in the intensity and timing of heat from the sun are the most likely cause of the glacial/interglacial cycles.
According to the popular Milankovitch theory of climate, the advance and retreat of ice sheets in the Northern and Southern Hemisphere is caused by changes in the Earth's orbit. That is, when our planet's orbit wobbles, it results in cyclic fluctuations in solar radiation intensity that influences glaciers on Earth.