Who checks a fee schedule for natural disaster damage before they sign up?
No one questions who is responsible if something happens to a car that they lease. Get it stolen or in an accident (your fault or not) or have it damaged or destroyed in a storm and guess who is responsible? The person who leased the car. To protect that person insurance is normally required. Who pays for that insurance? The person who leased the car.
Yet for some reason other leases are not treated the same way? If you go to Aarons or RentACenter and lease furniture and electronics and it is destroyed the lease company just forgets about it? No. They expect their customers to insure the equipment they lease. It remains the customer's responsibility. Perhaps in this case with a whole community hurting there might be some leeway (waiting for the FEMA money to arrive) but their usual policy is the same as DISH. Take care of what you lease, you are responsible for it.
And as far a PlayOn's offer ... isn't that worse? Turning a disaster where a record number (and growing) number of lives were lost into a marketing opportunity? As Seth Meyers would say, "really?" Their offer is a publicity stunt.
DISH will likely end up writing off many of the unreturned or damaged receivers. When they do it will be a private matter, not a PR stunt.