Well, Uncle Sam has an explanation.
The explanation is that contrary to basic economics and common bloody sense, the truth is (or so they claim) that Federal agencies really do give their officers the expensive combat ammo for range practice, instead of the more usual full metal jacket (FMJ) bullets, otherwise known as "hardball". That would be the kind of combat ammo that goes for more than a dollar a round at the store.
The agency [SSA] said it has 295 special agents across 66 offices in the country. "These investigators have full law enforcement authority, including executing search warrants and making arrests," the statement said.
As for concern about the type of bullets -- hollow points, which expand upon impact -- the statement said the type is "standard issue" and is used during "mandatory quarterly firearms qualifications and other training sessions."
50 rounds of Federal HydraShok (JHP) in .40 S&W, 165 grain bullet costs $67.00 at the first store I googled. Same store, 1000 rounds of CCI hardball in .40 S&W, 165 grain bullet, $400.00. Which is $20.00 for 50 rounds. Buying in large quantity, US government agencies will probably be able to get their JHP combat ammo much cheaper, perhaps only DOUBLE what they'd pay for FMJ at -retail-.
Sadly, I believe this explanation. It fits their pattern of "price no object" behavior perfectly. I didn't think they'd be wasteful enough to burn JHP at the range, nobody does that. But it seems I was wrong. D'oh.
Still no word on why Dept.s of Agriculture, Education and Housing need their own SWAT teams though. Same reason probably, mission creep and too big a budget.
"Never attribute to malice that which is adequately explained by stupidity." Robert J. Hanlon
"... but don't rule out malice." Robert A. Heinlein