Yes, this problem is quite obvious, and yes, I'm in favor of full-scale colonialism, but couldn't a heavier presence by UN/coalition-of-the-willing peacekeepers, with powers to override local authorities when it's needed to prevent open violence and abuse, also keep the scum that floats to the top there in check? What's the tactical record for peacekeeping operations that had a reasonably broad mandate for use of force? (Hmm, here's one account. My cached thought that a "firm hand" brought decent results in Somalia appears to be confirmed.)

...Of course I realize how unlikely any international body would be to approve such powers against the protests of an "independent" local regime (Somalia being an unusual case in that regard), so such policing of aid-receiving countries would have to be carried out unilaterally and without foreign oversight by whatever nation could be willing to implement it. Which creates a power dynamic that's basically colonialism. Which, again, would IMO be quite OK with purely selfish intentions and better yet with benevolent ones, but should be done openly anyway for clear generic reasons.