I guess that's kind of the dilemma. On the one hand, you could totally re-do these sites to be appealing and useful to their users, but if you're focus is on getting ad revenue more than actually being useful to people, that's doing the opposite of what you want. There's no reason for the owner to be dishonest here either, even if he provides "decent content", it's easy to see that's not why he made these websites.

But on the other hand, optimizing your design for clickthroughs is also a pretty good way to get blacklisted, so the design that works best for making money off of visitors, is also a long ways from being the best layout for getting more visitors to your site.