And then they sell you their add-on CDW insurance. Anyone with more sense than money takes out their own CDW separately (not the rental co’s over-priced policy) when they rent a vehicle. In Europe the rental companies will lock you in their booth for 30 minutes while they try to sell you this add-on.
Even if the rental costs do not cover this sort of truck damage, I bet the rental companies have it insured and their insurer will seek to recover from the renter. And damage to the bridge likely gets paid by the bridge’s owner’s insurer who then has to try to subrogate to the driver/renter. Of course if they claim via the rental company and those guys still have the renter’s credit card details…