Moral dilemma

Generally speaking, it is unethical to capture a wild animal for the sole purpose of "wanting it."

If they are not found within the hobby than I would say leave it in the wild. Unless you capture it only to study, then let it free.

These guys take a lot of space to form a proper orb web. There’s actually some occurance within the hobby and there are people in japan that keep similarly sized orb weaver species for “spider fighting” obviously, i wouldn’t recommend that last part, but the spider as a whole can be kept with the proper enclosure and care. It just takes a lot more effort than most other arachnids.
And of coarse, if we are completely honest with ourselves, we can all agree that the critter will fair better in it’s natural home than in our care. It’s just honest. That being said, there are plenty of people that keep WC critters.

For a detailed care thread check this out:
http://arachnoboards.com/threads/a-difficult-keeper-argiope-aurantia.310804/#post-2828362

Also if you’re just really interested in similarly large orb weavers, here’s a video in english about the japanese spider fights.