Rockstar Leeds wrote the manuals, I believe.
They aren't as huge on PR as Rockstar North is.
Also, the "stories" series wasn't so big, as you said. This was evident on a lot of GTA websites.
So, if the PSP games (and the PS2 converts) weren't doing so good online, I guess they didn't want to give webmasters a favour there.
Once a new technology starts rolling, if you're not part of the steamroller, you're part of the road.