The contract ones near OCs will often give you the SNI rate. Other than that, none that I know of have a "Schneider associate " discount. When we book a hotel for a driver it goes to a travel agency and they do the booking.
You should start your own company. Call it the Dax company then ask for the company discount , you would be amazed at how many service providers would be happy to give you a discount for the Dax organization.
I would not want to stay at any hotels that are the hook ups of any trucking companies.