These unethical sites are doing what is called "content scraping" - it's more or less a bot that goes in and copies all the content. It's alarming and it's pathetic, but you can (and should) file DMCA complaints each and every time you find an incident. Complain to the sites owner and most importantly to their web hosting provider. In many cases you can get them taken down. If the website happens to run Adsense ads you can also file a DMCA via google and they act on them VERY quickly. Unfortunately, in the case of big ezine and that debacle they do not run adsense.
I use copyscape and check for content theft. I found a young girl on an "experts" site who had lifted the content of my website word for word and used it as her profile. She was banned almost instantly from that site when I filed the DMCA with them. Within 2 hours my content was taken down.
All you can do is be vigilant and persistent because unfortunately it is a part of life with less than scrupulous people who have no creativity of their own so they have to resort to stealing.