I withdrew $8400 cash a couple of weeks ago to pay my friend/contractor for some repairs on one of my properties. So far no one has come knocking on my door.
Done the same a few times and not a problem and always paid contractors or vehicles with cash so I await for more of a respectable link before I get all in a worked up way.
To # 14:
Knock! Knock! Landshark! (aka IRS, aka Treasury agents)