Insurance Oversell!

On Friday last, I rang several insurance companies to try to get a better deal on an annual travel policy with my particular medical issues fully covered.
I promptly found one via Martin's Money Tips which cut over £20 off from last year's premium through World First.
The next one was £250 higher and the one after that £150.
With the last of these, I told the 'lady' that their price was 'out of the ballpark' and why. She insisted with a perfect assurance that I wasn't covered for what I wanted - even though I was staring directly at the precise details I'd been sent by Email as we were talking.
I told her this repeatedly and she argued and continued to do so until I had to turn borderline rude to finish the call.
Does lying to people and implying that you the customer are a liar or completely stoopid really sell insurance?