What Olly said. If you're going to use animals for a purpose that involves killing them, then treat them well while they're alive, give them a decent death, and make sure you use as much of them as possible.
So a rabbit hat made from wild rabbits which have been shot to provide meat is, if you take the meat consumption as a fait accompli, indisputably better than not having a rabbit hat from a meat rabbit. Of course a rabbit hat from a rabbit farmed in a cage and killed solely for its fur is quite easily argued to be objectionable.
Here's an interesting point, though:
Rabbits and other animals are essentially renewable resources. The fuel involved in their production is essentially just plant matter, which is itself a renewable resource. So a rabbit hat, even from a farmed rabbit, is an environmentally-friendly product. A garment made from synthetic fur or fabric, however, is made from non-renewable resources in terms of oil and the funny crustacean things that get dredged out of lakes hundreds of times quicker than they can reproduce, and those materials have been extracted by means which themselves involve further use of non-renewable resources.
So whilst farmed fur clothing can be argued to be ethically unsound, it can also be argued to be sustainable and environmentally-friendly.
Discuss 🙂