Very Expensive Insurance
The amount of money paid in claims versus the premiums paid is very small compared to typical life, health, auto, etc insurance which means the companies (and especially those PUSHING the warranties) profit greatly from them. I'm all for free market economy and am glad that many people chose to buy them because it keeps the prices down on the items themselves.
Maybe I've been lucky, but not buying extended warranties has saved me literally thousands of dollars in the past 20 or so years. You could fix a lot of items yourself if you just made an account and deposited the premium price into it after every purchase.
Ask yourself if they really care that much about you the next time the sales clerk is pushing the warranty so hard. No it's because of the nice commission they recieve from the sale.
Having said all of that, I'm sure my truck won't start now!!