Not much. Unfortunately, Gaia has become more of a business than a hobby for it's creators.
However, they don't know how to run a business.
I highly doubt it took over $11M to get zOMG running, unless they were overpaying themselves/outside developers. Secondly, when you run a large business, which is what Gaia currently is, you make investments. Let's say that it really did take $11M to get zOMG running. It's ridiculous, BUT SURE. You're looking at at LEAST five years before that investment starts bringing some return. That means it needs to bring in $2.25M IN ADDITION to whatever it costs to maintain zOMG per year to meet a five year goal. I also don't think that it brought in that much money per year. I don't think zOMG ever made enough revenue to bring any return on an $11M invest. It was more 'free to play' than any other game. In fact, the game was very easily played and enjoyed without ever spending GC. I used to do speed runs back in the day, and never spent any GC.
But, let's think about Gaia more like a supermarket, in terms of things that cost GC. There's mini-games, which are obviously a very small slice of the revenue. The biggest portion, of course, is the CIs, MCs, and gold generators, with things like Alchemy and the individual Premium Items falling somewhere in between. You might think, hey, it's good business to cut out that the least performing department and shift that attention to something making more money, that's a bigger return on the investment! And you'd be very wrong. Companies, not just supermarkets, do often take a loss on underperforming departments or even individual products (like turkeys for Thanksgiving) because they draw customers in. Think of zOMG as the deli/bakery. These departments NEVER generate as much revenue as grocery, produce, dairy, frozen, or meat departments. They require more labor, and can't calculate that labor into the mark-up. In fact, many grocery stores take a loss on the deli/bakery. Why keep it? It brings customers in. They come in for sliced meat or a birthday cake, and while they're there, THEY BUY OTHER THINGS, even if those other things are slightly higher priced than a competitors, because it's convenient. If that store didn't have a deli/bakery, many customers would go to another store altogether. Thus, taking a small loss on an underperforming department actually helps to generate MORE revenue for the store as a whole.
In short, Gaia is dumb for shutting down zOMG for underperforming; it obviously takes more money and labor to maintain than the CIs, but it was keeping people on Gaia when they might have left long ago. People are leaving the site in droves because of the hyperinflation of Gold, they can't be doing something dumb like sending people away.