My guess is Charlie really didn't want to add these low rated channels in the first place but had to during contract negotiations...which is why they were added just for this new Flex package and only in SD. Since hardly any one will have this particular package...he won't have to pay very much for them.
Very much along the lines of my guess - these channels would never have been added if they had to be in the Top packages.
What does the official press release/announcement by DISH say about what packages the new channels will be in?