Hello Theophanes. That's a great question. After being on HubPages for over 4 years I have witnessed a lot of copyright infringement (especially with photos) and a lot of copied work posted on other sites and blogs.
This activity is illegal and needs to be reported. The best way to report this is to alert Google and other search engines by filing a "DMCA Complaint". Whenever someone creates and publishes original content on a respected site (like HubPages) they receive a digital signature of sorts that acknowledges the author and content along with a date and time stamp. Anything that is copied after that, is not considered original.
To learn more, follow this link to HubPages Learning Center Article on How To File a DMCA Complaint: https://hubpageshelp.com/promotion/Learning-Center...
DMCA stands for "Digital Millennium Copyright Act" and you can also read more about that here: http://en.wikipedia.org/wiki/Digital_Millennium_Co...
About a year ago, this happened to me and I was so mad. I was alerted by a small group of other Hubbers that were attacked by another site where they stole our work and published it 100% as their own. We got together, complained to Google, and the site was eventually shut down and banned. You can't let copyright infringement slide.
If this happens to you or anyone you know, it should be reported to prevent future infringement. Great question that I see quite often over time.
Hope this helps! Best of success!