Don't you think it may lead to fraud as well because there is no third party involvement. For example when we use banks to do transaction, Banks should have to consider norms and regulation made by central bank but in decentralized system whom we follow and if something fraud happen and whom we target ?
Well, banks can get bankrupt, do money laundering and charge you seriously for your actions. Cryptocurrencies allow you to store money for free and perform transactions in a fast and cheap way. If you send money to scammers, nobody will be able to help you, but not because of decentralization, but rather because of pseudo-anonymity. And technically most of us still use third parties like blockchain.info, MEW or exchanges, so there are some authorities that could be blamed for internal bugs, system insecurity or scam. But the thing is that it's not right to seek for another party to blame. It's your money, your management. You are responsible for what you do and when anyway.