Not to defend Robert's position, but DTG themselves were very ambiguous with their initial statements regarding 3rd-party participation. That history is still preserved at AVSIM in their forum postings. Their original statements did in fact imply that all sales would have to be made via the Steam platform. My own initial contacts corroborate this position as I was being told that ~60% of the sales price would be divided up between Steam and DTG, with the remaining ~40% being remitted to our company on a quarterly basis.
It was only about nine months later that this position was softened when DTG began insisting that there was no requirement that 3rd party sales had to be exclusively available via the Steam channel, but could also be sold via the developer's existing sales channels. That was a significant change in policy, but still not good enough in my considered opinion. About seven months later, their position changed yet again with the requirement for the Steam portal being abandoned, and it was now apparently okay for anyone to sell for the FSW platform through their own existing outlets. I found it difficult to maintain trust any company who's position changed according to the direction the wind was blowing.
At this juncture I'd not yet seen the numbers of active users DTG had forecast, so I pretty much lost immediate interest in developing, especially so since the (partial) SDK had yet to be released. It was pretty much impossible to develop for FSW without the tools, so I adopted a wait and see attitude. Nonetheless, I did experiment with trying to get our C310R Redux Edition into FSW with limited success absent the SDK, but was not terribly impressed. I am hugely disappointed at the apparent failure of the management of DTG, and in no way cast any blame whatever on the passionate and dedicated development team they'd assembled. I do hope that they all find gainful employment elsewhere soon, especially where their talents are better appreciated!