It's a crime of computer / network intrusion. Not a crime of property law (you can't own a record in a database as property, and therefor I can not steal your property).
> if you're abusing a fault in the code, that's very clearly fraudulent behavior.
Another way to put this is that you are using the contract in a manner how it was defined by the author. Compare with a misconfigured web server showing open directories of files, or a robots.txt with a typo in it (ignore: /adminn). What is a fault and what is a feature? Who decides this? Solely the author of the contract? The parties involved (who splits the ties)? A majority of 3rd party volunteers? If everything is decentralized and open to anyone, whose computer network are you intruding/disturbing?
> doesn't mean that it doesn't fall into existing laws
If law was a software product, we are definitely a few pull requests behind its intended use. Look at how long it took to update authorship/copyright laws with the evolution of the internet, and how ugly things are when wrestled into the old framework of: I create it, I forever own it.