Coal mines still employ a great deal of human laborers, even the few that are highly mechanized. And it's still difficult, dangerous and not very pleasant work. Most coal mining is still done underground and even surface mining is quite dangerous. See e.g. <http://en.wikipedia.org/wiki/Coal_mining>;

It's also usually not a good idea to act condescending when you think you have superior knowledge, as then you may look foolish when it turns out you are misinformed yourself.