What they're selling isn't a warranty but a service contract that usually contains so many gotchas that they can wriggle out of paying for your car repairs. When a stranger calls to sell you stuff, the rule is to *never* buy.
This is extremely aggrivating! I have placed so many of these numbers on the blocked call list and told them not to call, also repeatedly making complaints with the FCC (as this number is on the DoNotCall listing).
I either get a robo dial, or a rude person who just hangs up when I am in the middle of stating to remove me and this number is on the DNC list.
Very unprofessional. They keep leaving a message at work but it's always just "1,2.3 test" and then some laughter before hanging up. Even if I were interested at one point this very unprofessional behavior would totally turn me away.