tangor - 7:11 am on Feb 23, 2012 (gmt 0)
a) Ethics aside, what gives them the right to frame a (my or yours) page and how can sites get away with doing that?
It's all about the ethics first. No one has the right to piggy back off another's labor. They can't get away with it with DMCA (whoops! Try making that work in China)
b) Is it "technically" a copyright violation given that fact a visitor can still navigate the site, but have the banner ad at the top?
Yup, but not quite so much... given that your site works, but has been taken hostage by another site for adverts. (Bring out the big guns... copyright claim/DMCA, even in China... just takes longer and more elbow grease and and and...)
Regardless of answers to these question, I want to remind everyone that this goes on and it doesn't hurt to put in a break out of frames script as a matter of practice. You might think you are
Yes, do that, just don't be surprised that JS diabled/NoScript browsers can't see it.
One of those hurt things, where copyright should be honored and is not... that anger felt is one reason why SOPA, PIPA, ACTA et al is getting so much traction in govs these days. These are observations of what is now and how it sometimes fails, and that only the strong will fight to retain their IP (intellectual property) rights. There are discouraging aspects (kill baddies in USA, UK, CA, AU and can't get any traction in CN, RU, RO, IN, etc... But if you treasure your work you'll keep after it and do not depend on a single bit of JS to "protect" your work. After all, they've already scraped it and can put of the page on their servers. As long as they can frame your site for the bandwidth presentation they won't go down that other path.
Web site development:
Two days (or more) to write/format/post (yours)
5 seconds to rip/frame into autogen slop site in another country
Note: I did not append "priceless"