Science Needs vs. Wants?

There is no guarantee that the study of practical applications will reduce more suffering than the study of the purely theoretical. Theoretical study leads to breakthroughs in the realm of practical applications. Further, none of us knows the future, so no one can predict what areas of science should be most rigorously studied. It's like arguing that no one should be writing fiction and that all authors should write only nonfiction, because that is real and has impact on people's lives, but all that made up stuff influences people, and so it has value. Scientific discovery is not a straight line, and results cannot be guaranteed in this way.