But the culture would be lost to what? Corruption is not necessarily robbery of public resources, but rather inefficiency, stealing and subdevelopment of some manufactories and production.
Also, culture is not necessarily something "rated", that can be higher or lower, but a more complex "feeling" of deserving and identifying to one's nation.
The only "valid" excuse to such corruption would be a border city, in which the population would be more tempted to turn sides. But this is already taken account: if a border civ's culture is higher than yours, and you do not make your people happy, then the city flips.
It is a good idea, but the game, IMO, has a better one.