if the fact that paying them more results in a better society, it may be worth it. The absolute amount is irrelevant if the return on this investment is greater.

A higher paid politician is also less likely to be corrupt (since the agent causing the corruption will need to beat their high salary, which is risk free). A higher paid politician will not need to worry about blowbacks from policies that are good for society but bad for existing entrenched players.

And a higher paid politician may encourage people, even if they were poor initially, to work to become a career politician (and study it, the same way a neurosurgeon or any other professional trade would). High pay almost always equate to high intelligence, and i would hope that an intelligent person is also someone who can run things better.