To some extent, I would argue that we're living in a science-dominated age, where people aren't willing to believe that anything other than cold, hard facts could be applicable towards life.
The more obvious response, however, is that a lot of university courses require subjects such as Chemistry and Methods, leading people to take them. Also, in terms of sciences, there are only four/five (depending on how elitist you are) real subjects. In contrast, for humanities students (which is the core student-base for subjects such as Geography), there are many more subjects you can take, meaning that said students get spread out more widely, leading to smaller, but more plentiful humanities subjects.