Their business was built partly on easy returns. My guess is they've run into a fair number of customers who aren't that good at packing things for mailing.
Neither is Amazon for that matter.
I once had to send back an empty package to them for a refund. It was a blister pack and the plastic had come loose from the cardboard backing and, as a result, the actual product had fallen out prior to it being shipped to me. The product was not in the box and there was no way it could have slipped out of the box, so they had to have shipped an empty blister pack to me.
Which I then had to send back to them for a refund and Amazon also refunded my return shipping charges which meant it cost Amazon the return shipping charges as well as the cost of shipping the replacement product to me.