But they might out of cultural factors. (Also, poor nutrition, in the aggregate, could harm national IQ and mental health, among other things.)
Corruption is a norm, it can be removed (Singapore) by sufficiently-determined group of actors passing and enforcing the right laws.
The trick is that it’s based on expectations about others engaging in corruption and expectations of getting caught. It also arises when it’s impossible to function without violating the rules.
When corruption rates are high, there is not only a social expectation that one will get away with it, but there’s also the effect of “but everyone else is doing it - why do they get to benefit, but not me?” Additionally, there are networks of corruption that can be relied on.
Increasing the odds of getting caught and punished above a certain level eradicates the pro-corruption network effects. (This could be achieved with a series of sting operations all unleashed at once as a form of shock therapy.) At that point, corrupt officials become isolated individuals with far less expectation of getting away with it.
After a while, the next generation of bureaucrats rises in which the default is that corruption is almost unthinkable, and the relative rarity at that point makes it much less costly to police.
Under Communism, because it’s so at odds with reality, arresting the corrupt officials won’t work as well because they may have to lie and be corrupt to survive, normalizing corruption. Similarly, some cultures with a strong external locus of control or other elements may be prone to corruption.