What do you all think of Linkslist/Directories using the Nofollow tag?

[Allfetish]

What do you think of linkslist/blog directories/trades using the NOFOLLOW tag for all the user submitted links? Basically what this means is that search engines will not look at your link at all based on that particular page. In other words, to the search engines it is as if YOUR LINK DID NOT EXIST ON HIS SITE. For more info on the tag, go here: http://en.wikipedia.org/wiki/Nofollow

Should people using these tags without disclosing it to you be considered "cheaters" ? Does anyone know of software which will not only check for te linkback but also check for the nofollow tag not being present?