Yes, exactly. This thread is just speculation. Poloniex is based in the U.S. and needs to pay the IRS taxes. The money that they owe from their .25% trading fee would make creating "fake volume" very costly for them, so really the entire notion doesn't make sense. They could be actively trading I guess, but that is a different thing.

Source: http://coinmarketcap.com/exchanges/volume/24-hour/

Nearly 300 million in daily trade volume, their high rollers pay less in fees but Bots are market takers so a conservative estimate would be them getting .14% average of fees. That would be $420,000 a day in earnings. Now if most of that was "fake," they would be on the hook for a shit ton of tax dollars at the end of the year. A tax bill on earnings of 154 million dollars, no matter how many right offs, would be prohibitive if they were not actually earning that money.