I've been in the situation of not being able to tow with a rental vehicle. I was involved in an accident that was not my fault. When my SUV went into the shop or repairs the other person's insurance was only going to provide me a car. I told them I needed a truck because I had a trailer that I needed to pick up. I was provided a 2002 Silverado 4x4 extended cab with tow package. When I picked up the vehicle they told me they didn't allow towing with it. So I had a brand new truck with a tow package but not allowed to tow with it. I'm sure if I would have had an accident while towing the insurance would not have paid out since the rental company did not allow towing with the vehicle.