NOT A STUPID QUESTION Flyertalk has had some threads on this issue.
In the past some rental agencies listed valet as an additional authorized driver. Presumably the valet company is adequately insured and will assume liability
I lifted this from a recent post on flyertalk
https://www.flyertalk.com/forum/33802333-post22.html
Plain and simple, the answer is NO. A valet attendant IS NOT AN AUTHORIZED OPERATOR. I worked at Hertz up until recently. I was a higher level manager (I won't say at which level, but you can make assumptions based on the fact that I managed 250 employees directly, and up to 400 indirectly.) I have intimate knowledge of the internal processes.
If a valet damages a vehicle, the customer receives a report from the hotel valet. We process the damage report for the customer, and regardless of whether the customer took the LDW, we ALWAYS pursue the customer. Should the customer choose to pursue the hotel, so be it, but we always pursued the renter. Reason why...the LDW is invalidated as soon as the keys are given to an unauthorized operator, 100% of the time.
Think of it like this...makeshift parking lot attendant set up outside of a stadium that charges $100 to park there and hires local homeless guy to park cars for 2 hours. That attendant is a valet attendant. It's the same thing as the Valet Attendant at the Bellagio, however, i'm fairly certain that the Bellagio would have little issue reimbursing the renter (hotel guest I'll assume.) Either way, Hertz does not communicate with the third party (valet) and will only hold the renter responsible. I have personally placed renters on the DNR list (do not rent) for giving keys to the valet at their hotel resulting in an incident. That happened often enough that it wasn't a one off situation either. If it was a President Circle customer/ 5 Star, they'd be reminded that they should follow the terms of the contract, but if it was a one time renter (or a Hotwire/Priceline type of renter), its automatic DNR.