Or is it generally believed that images are of less "value" than video?
To get an image you don't even need to do anything vaguely hacky like Ctrl-U: you can just take a screenshot of your desktop. Pop open your favourite image editor and crop it: job done.
The best way to protect images on the web is to a) watermark them b) have them in low res.
But the general point is: if it renders to your screen it can be copied.
Any good player framework will likely account for this, hopefully by allowing all the same DOM-ey calls that one could perform with HTML5-ey video to be performed on flash through some sort of wrapper.
I don't think that content companies will just let it happen.