Every so often someone writes an essay on why Superman doesn't just stop social injustice or whatever. My response is that since superhumans are still only human in the ways that matter, they can make mistakes. If you stop crime, that at least puts a lower bound on how bad your mistake is. It's pretty obvious that stopping Dr. Octopus benefits people--the chances of being wrong about that are nil.

If the superhero starts overthrowing governments--or promoting cryonics--there's a chance he could be wrong and screw up. And if someone with such an influence screws up, he really screws up.

Reading that fic from a point of view of someone who doesn't support cryonics makes it clear exactly why beating up super-criminals is the best use of his powers.