If you pay them enough money you can sign a custom contract with them that means you can sue them to pieces if they are later found to be storing your original content despite saying that they aren't.
Personally I've decided to trust them when they tell me they won't do that in their terms and conditions. My content isn't actually very valuable to them.
Personally I've decided to trust them when they tell me they won't do that in their terms and conditions. My content isn't actually very valuable to them.