I never get uptight. There's nothing in this world that is ever worth getting up tight or happy or sad or anything, about. On average, I'm relatively emotionless. Even when I *seem* upset, I'm really not because everyone will do whatever they want regardless of how much I yell and scream, so why bother? Apathy is my universal world view.
Back to the issue at hand. It seems as though the sources you quoted, at least the way I read it, indicate I was right. The high cost was in the tight environmental controls needed. First, as the name suggests, anaerobes can not function with oxygen. So all oxygen must be removed. Plus this particular type, must have a temperature of around 95F. Also, these have very pH-sensitive (pH 6.8-7.4 optimum).
What makes it worse, the process requires two kinds of bacteria. The OTHER kind of bacteria has a byproduct of changing the pH balance.
So the key is in the expensive special environmental containment that maintains these optimal conditions. Now once you get past the initial investment, then it's great! The system works nearly forever with almost no maintenance cost.
The last thing I see is that this will supply only enough gas to cover the energy needs of the farm, which is why farmers have signed up for this by the dozens. But this, least by the energy estimates on Missouri site, will provide free energy for the farm. That doesn't cover the needs of society.
Land fill gas, has a large number of groups against it. I am not clear on the details because different groups have different views and data. The claim is that land fill gas contains halogenated contamination that includes: fluorine, chlorine, bromine. These can form dioxins which are of course toxic. Again, I'm fuzzy on the details, so I don't know how legit this claim is.
http://www.energyjustice.net/lfg/ This is one of those groups.
Information also suggests the cost of purifying land fill gas is a bit high. The reason is because some of the impurities commonly found in land fill gas, is highly corrosive and will destroy gas lines. Thus the cost of gas production from a land fill is vastly higher than of normal sources. So what has happened in floriduh is, the government pays the company in subsidies to collect the gas.
I am always amused by this logic. If you live in floriduh and use natural gas, your government is taxing you, and giving that money to the gas company to collect gas, that they then turn around and charge you for. I want a job where I'm paid to make something that I am then able to sell at whatever price I want to the very person who paid me to make it. Only in America.
BTW, 90 to 95% of the greenhouse effect is cause by water in it's three forms. Of the remaining 5 to 10%, the vast majority of it is CO2. Of the remaining 1 to 3% is trace gases, of which only a fraction of that is methane. The likely world temperature difference of methane is at most 0.01 Celsius. In other words... not worth considering.