By this logic, people who do not drive should not pay taxes for road repair, or that people who don't have kids shouldn't pay taxes for K12 schools, or that people who have replaced their original bodies with titanium robot hulls shouldn't pay taxes that fund the NIH. Of course we would have problems if this is how it worked. Minus the robot people, who I just made up.
You are right that a person might not directly take advantage of a state university that is paid for in part by their taxes. So to that degree, they're not directly getting what they are paying for. But their taxes help educate others in their state. Presumably it is more economically and culturally advantageous to have an educated population than not. But it is hard to quantify those benefits (because people value things differently), which is partly why we have the argument in the first place.