I'm not going to get out of my car for deliveries
Is there a reason that you don't want to get out of the car?
Because I'm too lazy to do. Also, those "reps" will do their deliveries anyways no matter what I do or say.
At most places delivery personal will bring their packages directly to the customer so this should just be expected.
They shouldn't be doing their jobs when I don't get out of my car.
If you don't want to do the job, then  you should find a new one. If you continue to be a delivery person, it is expected you will get out of the car.