I hear what you are saying about the possibility of gain, but bad things happen to those who misrepresent, especially when you are dealing with federal requirements and IRS. The possibility that a company would take the risk of possible federal investigation over a couple of hundred dollars would be incredible. Remember the old adage: "Don't be too hasty, what may seem like sabotage or deliberate misinformation is most often simple incompetence." Having dealt with Informa's very-slow-to-respond accountant and the vague references to "checking with corporate" leads me to believe their right hand may not know what their left hand is doing.
Not a bad company to work with - as I said my scheduler is awesome - but when problems happen, it has been my experience twice that they do not handle the problem quickly or well.