I use publicly available proxies all the time. I scrape them or use some of the subscriptions I've bought along the years. My question is : why does any company or individual keep an open proxy out there? Seems to be a complete waste of resources and a risky thing, considering the proxy could be used for illegal stuff. Been doing black hat SEO for years, but I never found an appropriate answer to that. Personally I wouldn't ever put an open proxy out there.