Search my ID you should find a very detailed article about our experience on the hailstorm damages sustained at Yellowstone - at the end, MC paid $2282, we paid $320 for non-covered, or dispute items. We could have paid $16 a day for the 5 day duration, total of $80, for FULL coverage and avoided all the headache, hassles, and at the end, higher costs we ended up with.
It really depends WHERE you go.
We declined all insurance coverages in our subsequent trips that including frequent one day rental between FLL and MIA, a 2 week rental at Pacific NW, and a 4 day rental in Scotland. However, if we go NP trip again, and in the season that would have hailstorm potential, we would BUY insurance.