Yes, aside from snow in RNO itself, rental companies know a high percentage of renters will be heading up to Tahoe and environs, and will equip accordingly. If you rent in Sacramento or San Francisco, chances are much lower.

Once when I lived in RNO, I had to drive to Oakland, and my windshield washer pump broke. I got it fixed at a shop in Oakland before I drove back home. I told the service rep I was driving back to RNO via the pass, but the message obviously didn't get passed along, as the person who worked on the vehicle topped to washer reservoir either with plain water or stuff rated to a not-very-low temperature. When I first sprayed the windshield, the stuff froze to ice almost instantly, and it took a couple minutes of front defrost fan set to high temp/high speed to get the ice melted.