not to imply no-one ever spectacularly fucked up their accounting software the old-fashioned way, but Amazon suddenly billing customers over a billion dollars apiece for routine S3 usage certainly does have a certain... vibe, doesn't it?
I have a growing pile of FedEx envelopes in my table which I believe are asking me to pay for some tariff or other. I recycle them, unopened, regularly.
Be careful. The reason I will never willingly use FedEx is that I had FedEx send a debt collector after me. A package shipped from me (and paid by the recipient, with a pre-paid return sticker) had the billing information printed in too pale ink for their automated system to read, so they tracked it as paid-by-sender. After they collected the package, I got sent a bill. After multiple rounds of my telling them that the seller had a corporate account with them and it was supposed to be charged to that account, they sent the bill to a collection agency.
I had to threaten the agency with criminal charges for demanding money with menaces to get the issue resolved.