Er.. sorry, but what do those links prove? The first two are open source programs, but have really never seen open source stuff on sale before? There's nothing illegal or suspicious about it, if the developers haven't exactly forbidden it.
The third link is only speculations by people who haven't done any research on the matter. Comments like
"Its basically pirated software that somebody puts on a CD or DVD and mails it to you and charges 5 bucks. Its very illegal. I think?" are useless - the fellow makes a strong statement, and then questions it by himself. I think?
I'd say it'd need some hard evidence before the webstore can be deemed *SCAM* as they did on the forum you linked to, instead of just guessing and speculating.