However, we still need these mind-boggling or theory-heavy experiments because we'll never know when they might make the next big discovery that is important, applicable and beneficial to mankind today or in the forseeable future.
There was a time when the study of astronomy or relativity, lead to important discoveries like how the Earth was not flat or that astroids might wipe us all out one day, or that the moon affects our tides, or that nuclear reactions in the Sun can one day provide us with electricity in our homes or et cetera... But as time goes on, more and more of astronomy or the study of relativity becomes increasingly abstract and who knows when or if it'll ever help us. We should still keep at it though. Once again, there should be no right or wrong on the issue.
Just want to clarify a point that I made in my post above: I don't think 'theory-heavy' sceintific research lacks 'applicability'. Rather, I wanted to emphasize that as time goes by, (and as we dive deeper and deeper into advanced/abstract theories and concepts) it seems to take an increasingly longer period of time for the fruits of such research to eventually find their way into application. There are always exceptions against the arguement of course.
Sometimes, research ends up in dead-ends but even when such failures result, we understand more of what's right by knowing what's not. The very fact that such research is being funded, shows that at least someone with the authority of funding approval thinks it's justified.