Many people have noticed that it's more profitable to use their cash to buy Steam Games and sell them to players who only wish to spend ce/cr.
With a little patience and marketing skills, you can even double the amount of CE you get for every dollar. Normally, it would be roughly 250CE/$ (calculated based on smallest CE pack).
And some people can even sell for 600-700CE/$ at maximum.
This means players sink money into Steam to get their CE rather than buying straight from OOO. No CE actually goes in or out of the system, and no money is actually sent to OOO.
Now with the promo, if you sell the box you can compensate for that, but it ain't gonna last forever.
Will this end up cutting OOOs profits A LOT? Since some people who do that, are people who sink quite a lot of money, money that doesn't go to OOO.
No CE actually goes in or out of the system, and no money is actually sent to OOO.
That's not really accurate though.
For the former, well, we have to assume that the player buying Steam games for CE is actually planning on using that energy, so energy is getting drained out of the system. Either that or they're stockpiling CE just to look adoringly at it. In which case it's still out of circulation - just in a really weird way.
For the latter part, OOO already have their money. In order for F2P to get CE they have to buy it from other players, either through the market or over trade. Either way, that is CE that has already been paid for, which means that yes the CE was brought into the system already. Besides, such a market for trading Steam games for CE cannot possibly exist without people buying the energy first direct from OOO.
So the net effect on OOO's profits is exactly zero. If a seller gets 5000 CE in exchange for a Steam game, that's still 5000 CE worth of $$$ that's already gone to OOO. Your assumptions would only work if by increasing the CE:$ ratio that the extra CE just appeared out of nowhere.