To be honest I have never ever seen a Rabbit housed indoors in my country, maybe breeders only, reading the posts those of you who do have them housed outdoors, take wonderful care of them, they are indeed spoilt, so I donot think these particular bunnys are being hard done by, they are loved and well provided for.
As for cats, oh YES they do indeed catch and eat bunny's, we had a wild one in the section once, we went a way for a holiday and my neighbour said she saw a cat catch it and run away with it. they do indeed pose a threat to the safety of your bunny if not housed correctly, there are dog-cat proof fencing material that would be most effective on a hutch.

I can well understand your concerns, maybe a kind word to them regarding this might be appropriate, as Karen said education is the way to go sometimes.