This is also how Los Zetas formed. A bunch of elite soldiers figured out they could make a lot more money as enforcers for drug cartels.
And then very quickly figured out that the "drug cartel" bit was the easy part and they got rid of their employers rather quickly.
The whole Zetas story is a fascinating one. If only their employers had read The Prince:
"Mercenaries and auxiliaries are useless and dangerous; and if one holds his state based on these arms, he will stand neither firm nor safe; for they are disunited, ambitious and without discipline, unfaithful, valiant before friends, cowardly before enemies; they have neither the fear of God nor fidelity to men, and destruction is deferred only so long as the attack is; for in peace one is robbed by them, and in war by the enemy. The fact is, they have no other attraction or reason for keeping the field than a trifle of stipend, which is not sufficient to make them willing to die for you. They are ready enough to be your soldiers whilst you do not make war, but if war comes they take themselves off or run from the foe; which I should have little trouble to prove, for the ruin of Italy has been caused by nothing else than by resting all her hopes for many years on mercenaries, and although they formerly made some display and appeared valiant amongst themselves, yet when the foreigners came they showed what they were. Thus it was that Charles, King of France, was allowed to seize Italy with chalk in hand;"
Unfortunately professional armies fail the one test that matters these days, which is the number of opportunities they provide for private actors to siphon money into their own pockets. So we have decided to ignore the lessons of history, because private profit today is worth social collapse tomorrow.
It won't stop everyone, but done correctly it could stem the most egregious of revolving doors.
I think it's very likely that entities like drug cartels already pay for things like location data for DEA agent's cellphones.
It was new information to me but supports your idea.
[0]: I'm not saying we shouldn't have a welfare state, it's clearly necessary in the modern world, but the America of today is nothing like the America that was intended, for better or for worse.
And a permanent, standing, large, and fairly dysfunctional (look at descriptions of military leadership and its civilian oversight in WWII and earlier, then look at same in Vietnam, then look at the linked Afghanistan Papers documents in this thread re: same in Iraq and Afghanistan) US military is even newer, only 80ish years. Even more recent if you consider its modern form to have taken shape only after the Vietnam draft ended.
I think the whole idea of the US being the world's most powerful country and acting outside our borders would have been something the founders would have struggled with, because they fought a war to get away from the world's most powerful country.
I wonder if the civil war counts here.