I realize it's easy for me to say, because I am not in the quarantine area, but picking a buffer zone and eliminating potential disease carriers within that zone seems a prudent thing to do. Could it (literally) be overkill? Possibly. But if they guess wrong and leave flocks in place, potentially many more birds could die if the infection spreads.
It is truly horrible for those in the mandatory kill zones and my heart goes out to them. I can't imagine how hard it must be to see pet chickens killed, not because they are infected, but simply as a precautionary measure. As other people have said, if the disease spreads, and I find myself in a mandatory cull area, I will kill my chickens myself, rather than trust the task to anyone else.
I think what is also upsetting to many people is the knowledge that a few irresponsible people were most likely the cause of this. From the government reports it seems like only a tiny fraction of the positive cases have been in "non-commercial laying chickens", yet law abiding chicken owners have had to see their flocks destroyed to help stop a problem created by others. However necessary it may be, it just plain stinks, and I can understand why emotions are running high.
Finally, I wish there was more transparency from the government as to what a "backyard exhibition chicken" is. If it is true, as at least one article I read suggested, that it is referring to game cocks and the disease is overwhelming found in large rooster flocks, I would like that to be acknowledged. Not because I enjoy pointing fingers, but because I don't like the perception being created that "backyard chickens" are a public health and safety problem. Along that vein, I've seen articles wringing hands over how children are getting salmonella poisoning from backyard flocks. I don't want this horrible disease being cited as a reason why all backyard chickens should be banned or excessively regulated. Also, if the disease is being most widely spread by the sale and fighting of roosters, I would like to know that the government is directing proportionate resources on curtailing those activities, so that the sacrifices people are making with their own flocks to maintain the quarantine will not have been for naught.
Really praying that they are getting this under control now, and that the end is in sight.