However, I would surmise that a better educated society, having learned how to apply rational thought, would reduce the likelihood of that occurring and/or would minimize the damage when it does (and it would.)
Their own benefit is 1) getting re-elected, and 2) being remembered through history as one of the great leaders.
Politics are a horrifically inefficient and error prone way of enriching yourself. To the extent that politicians value money, it's usually about getting elected again, possibly to pursue higher offices where they think they can have more impact.
Our corruption problem is not so much about money for politicians to spend personally, but to spend on further campaigning.
However, won't educated people in power make informed decisions for their own benefit?