I actually said that to a car rental agent once. He laughed politely and said that he used to hear it several times a week, but not so much anymore.
Hopefully he was able to not only TAKE the reservation, but actually HOLD the reservation.
I’ve never been hassled for supplemental insurance beyond the mentioning of it. There was never a hard sell and when I said I had my own coverage that ended the matter. I don’t understand the part about not signing or initialing anything. Surely you have to sign the contract and initial any options you’re declining. IIRC, around here anyway there are multiple supplemental options and with Enterprise I’ve had to initial three different boxes to decline them all.
BTW, keeping in mind that insurance policies and regulations differ from one jurisdiction to another, around here, and I believe quite commonly, the coverage that your own insurance provides on a rental comes from a specific optional endorsement that is premised on the liability agreement in the rental contract. This can be a very significant legal technicality if you try to claim coverage on, say, a borrowed car, or a courtesy car that was loaned to you by your dealer or mechanic, because if something happens to it and there isn’t something on paper establishing your liability, you may have no basis for making a claim and may find yourself with no coverage. This is the basis on which they often claim that such endorsements cover rentals but not loaners. So if someone lets you borrow their car but makes you sign a legally binding statement of liability for damages, believe it or not, they are probably (if perhaps unintentionally) doing you a favor if you have the non-owned automobile endorsement!
I just got back from a little trip to WI to see family. Sure enough, Alamo tried to bully me into buying insurance by implying all manner of dire things. When I finally got a little testy with the guy, he stopped, but he then tried to up-sell me into a more expensive car. That’s normal for them, but he was fairly persistent. I finally said, “Look, I’d like to get going, okay?”
This article describes auto rental insurance offered by major credit cards. For example, Visa covers physical damage, theft, loss of use and towing for those using any of its cards.