I've encountered this issue recently for the first time.
Usually, there is a deposit pre-authorized on the card. The additional insurance plans would lower the deposit (to a few hundred for fuel basically). I usually take the insurance plans anyway because I've had bad experiences that made me happy I had it.
Now, I was in a place where rental companies required credit cards except for the lower end models.
It took me a few attempts for one to realize that I would take the additional insurance anyway.
Usually, there is a deposit pre-authorized on the card. The additional insurance plans would lower the deposit (to a few hundred for fuel basically). I usually take the insurance plans anyway because I've had bad experiences that made me happy I had it.
Now, I was in a place where rental companies required credit cards except for the lower end models. It took me a few attempts for one to realize that I would take the additional insurance anyway.