I feel like a lot of professions do deal with math but are more practical for econ or finance or CS majors. So What can you do with a math major without double majoring in anything? Is there any upside to majoring in math over econ/finance?
It depends on what you want to do really, but in the end every job in industry will be applied math of sorts. Academia is another common route for math majors.
Math degrees can be beneficial for someone in a field like Data Science and for someone who self-learns CS, a math major can give them an advantage in theoretical areas of computer science. There’s also actuaries, who are specialized math majors.