There are plenty of successful businesses operating on the open side of the web.
That many users continue to tolerate failures like Mt.Gox is just a sign of how immature the market still is. There will be many successful ventures that fully conform to regulation. And any business restricting itself to operation on the darknet is limiting itself to an extremely small segment of the user base.
I simply cannot see how it's possible to conform to 100% of regulations and laws in good faith (that means NEVER paying legal or illegal bribes). http://www.amazon.com/Three-Felonies-Day-Target-Innocent/dp/1594035229
If "successful" is defined as "merely hasn't been targeted by arbitrary, capricious, or malicious actors YET", then sure, there are "plenty of successful businesses". Such luck, or whatever you want to call it, is not equal to immunity.
Immunity is gained by having the resources to lawyer up and fight.
Welcome to the American dream.
Or nightmare, if you beg, borrow, and steal to get a lawyer, and evil still wins, as it almost always does.