Extended warranties are highly profitable for companies. If an unexpected repair would put someone in a serious bind, then the cost of the warranty would be the morale equivalent of an insurance premium. If you need it, go for it.
That said, I just bought a new Suburban. When I picked up the vehicle the nice folks at the dealership tried their hearts out trying to sell me an extended warranty. . They finally gave up when I told them, and I'm really serious about this, that the money I have saved over decades of not buying extended warranties probably paid for my new truck!