Yeah, I guess I was a little harsh in my assessment - likely due to the unwelcome nature of these offers. I doubt many of them are outright scams - selling swampland in Florida. But ISTR I used to get a number of the “You have already won!” type, which definitely have a sizable element of scammishness.
Most often, I suspect they are simply something that I do not need or want. I suspect some portion of them might be “not particularly good deals” such that, if you really wanted the service, you could shop around and get a better deal. Of course, that would cost you time and effort, compared to receiving an incoming call.
Glad you had good luck with the extended warranties. At times I will go back and forth on those. My understanding is that with ext warr you are basically gambling against the provider as to whether or not you are going to need services exceeding the premiums. The dealer/financier is betting you won’t. And as a general rule, I figure as long as I have enough savings to cover the anticipated repair/replacement, I’m safe not taking the wager. But I am FAR from expert in consumer financial matters.