FX Broker Restrictions

Is there some retail broker who would allow you to trade at more than one currency pair with exactly the same position i.e. instead of squaring the the position like

USD - gt; EUR USD,


I am able to execute

USD EUR JPY USD?

The brokers must allow us to do that. I can't understand why not...?
Its FX, thus we should be able to convert one currency to any other. That's the essence of the market, isn't it?


P.S. I have done my research to understand that trading in Arbitrage is banned by retail brokers. So that isn't my goal (though ideally I would really like to...I would really like to grasp that risk free money that is there all the time). However, I am guessing just the large banks and the hedge funds have the ability to accomplish that. (some comments are welcome...)