In the middle of the noughties...
... I had a call from a company that had contracted one of these "external support services" for their smallish - ~25 seats - shop. After suffering some issues with their file servers, they called "support" and spent several hours on the phone, to no avail. After several days of tests and checks, the customer called me to be their "interface" with the support service, as the guy in charge of that was more of a power user than a professional IT guy, and paid accordingly (peanuts, monkeys, management cutting corners, ... you know the drill).
I went there, studied the issue for a while and told the customer I could fix it myself, but the customer insisted I call the support service, as that would supposedly save time.
To put it short, their setup included two servers, one of them a Windows 2003 server and the other a Debian file server. The support guy wasn't even aware of the existence of the Debian server (or the existence of Debian OS :-). To add insult to injury, all the bushwhacking with the Windows server had caused more issues. At that point, I told the support guy that I needed to leave the premises for several hours and would contact him later. I was lying through my teeth :-).
I went straight to the management and explained them the issue, i.e. that the "support service" they had hired was basically a bunch of noobs with scarce knowledge of Windows servers and no knowledge at all of anything else IT related. My Unix/Linux was a little bit rusty back then, so I had to google the fixes for the Debian server. It took me another three hours to fix everything.
After being profusely patted in the back by the customer, I advised them to drop the contract with the "remote support". To this day, I still use this as a cautionary tale against those
scams "remote support services".
More recently, I had another funny experience where the support service was trying to use Teamviewer to fix a problem with a raid array. I had to explain the poor sod at the phone that you can't access the system BIOS using Teamviewer. :-D