Since quite good portion of various hacked attempts against Snitz are from my country, I can briefly answer about "why some sites are targeted"
First answer: Because they can... It is not generally important the topic of these boards. They don't even find their own exploits. They find exploits from various exploits sites or boards and search Google for the boards who can be targets. Searching "Snitz Forums 2000" can get you quite good list of Snitz boards open for targets.
Second answer, ofcourse to show off. They are not often older than age 20, often manupulate nationalist or religious sites. Most even does not know English. So the cheering crowd for them does not do. It is often shown to public as "virtual military". They can claim "They did anti-(insert their own nation or religion) site, so we hacked" since not many know English, they can easily sell such pathetic actions.
Ofcourse, there is good portion of site owners who does not follow guidelines of products they use or updates. I think they need to change mentality of "If it is working, don't touch it"
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