Walter van Kalken said:

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compromising the mail server. This is pretty serious stuff. Web proxies *should not* be open.

In your rosy world yes. Now try real world Millions of people are in countries were their providers do not care about this. Nor will they care because they do not have to listen to normal people. Thailand is such a country. Count the rest of SEA and China in there as well. Not all will be using open proxies though. But fact is as opposed to Western countries, in most Asian countries you cannot complain to companies as they'll tell you to shove it. Even western companies like JW Marriott do the same. They have double roomrate one if your Asian one if your white. It is common practice here. People complained to JW Marriott in Thailand. They told them to shove it. So people threatened lawsuit against parentcompany than they bowed down. But JWM is foreign owned so you can threaten with that. Most IP's in this region are not.

All of the above is no reason for Wikipedia to permit compromisable proxies to post. We'd be just spreading the problem outside Thailand and into the rest of the net. Believe me, there's nothing rosy about my view, I'm just determined not to permit bad practises in one or two countries to degrade the whole internet.