The main distinction between geothermal energy and fossil fuel energy is traced to the earth's heat. The quantity of heat extracted by geothermal plants is small compared to the heat in the earth's core. The process is quite natural.
In comparison, fossil fuel energy is obtained from the fossilized remains of living things mined and drilled from the earth. It requires millions of years for fossil fuels to be replaced. We may run out at some point, maybe even soon. The extraction of fossil fuel energy is harmful to the environment and can be dangerous to animals and other organisms. Drilling for this type of energy often results in oil spills, which is detrimental to the ozone layer.
On the contrary, geothermal energy has little impact on the environment, and whatever effect it may have, it certainly is not negative. Most of its waste is steam with a very minimal amount of gases that were trapped in rocks. This type of energy is championed by people believing in preserving the sanctity of the environment in which they live and the dignity of mother earth.
Geothermal energy also costs more, so it has not become the mainstream or primary source of energy. Fossil fuel energy has many uses, such as electricity, power vehicles, and massive machinery industries. In contrast, geothermal energy is used mostly to generate electricity, as other uses may not be feasible.