If you're like most Americans, you've probably received a robo-call about buying an extended auto warranty.

The Wall Street Journal reports that a group of web vigilantes decided to take on at least one of the operations bugging people. Before we go any further, please know that Clark is not recommending this vigilante action.

Word of the guerrilla campaign spread through a website called ReddIt.com. One specific target of the effort was Auto One Warranty Specialists Inc., located in Irvine, California.

The vigilantes essentially filled up the company's phones with junk calls so they couldn't place anymore outgoing calls. As one vigilante told The Wall Street Journal, "If you get a bunch of people together, you could blow up their voice mailboxes."

The owner of Auto One says 90% of the people who went vigilante were never contacted by his company. Ah yes, but he hires third-party companies to make the calls!

This owner is a known criminal who was convicted in 2000 of mail fraud and tax evasion. He declined to discuss his criminal history with The Wall Street Journal.

Meanwhile, the FTC recently filed a lawsuit against 3 similar operations -- 2 in Florida and 1 in Illinois.

The FTC's suit alleges the 3 companies made over a billion calls since 2007, generating over $10 million from people who didn't even have expired warranties. They're also accused of illegally blocking caller ID; calling people on the federal Do Not Call list; and blanket-calling area codes in metro areas where people don't even own cars.

Let's take a moment and review about warranties. Clark is not a fan of extended warranties in general, and he's only neutral when it comes to car warranties specifically.

If you can afford the potential cost of a car repair, you should never buy an extended warranty. But if you're unable to budget and save for repairs, then you should only consider buying the manufacturer's own warranty. Do not buy a third party warranty.

And if you stick to Consumer Reports' annual recommended list of vehicles, you shouldn't have to buy an extended warranty at all -- even if you have budgeting difficulties. The odds are such that their recommended vehicles won't have severe problems over time.