why would all 4 tires wear out on inside only

Hello, I have never heard that run-flat tires are known for this... What causes this is camber (amount the tires lean inward at the top), or toe out (tires steering slightly away from one another) I would ask them to check the alignment once the new tires are installed. Run flat tire issues mainly result from lack of proper inflation, but that would typically lead to wear on the inner and outer edge of the tires. Lastly, there may be too much weight in the vehicle, or the lower ball joints all the way around could be compromised.