Packlite can probably answer this better than I can.

All three of the sites you mentioned are part of the Amazon affiliates program; they disclose it on the front page of their website or in the "about us" tab. So, basically, they're shilling for Amazon products and all of their gear links take you to Amazon to buy; they receive a commission. I don't know who furnishes the content for these sites, but my guess is that it's not original with the site. I also noticed that there's no "chat room" on these websites - don't want to take the chance that somebody will trash their "choices," I suppose.

To me, they prove two things:
1. Anyone can set up a website.
2. You can't fix stupid.