It's putty's own fault. They used to (and perhaps still do) have a section on how they don't want your donated domain - they like their current one.

From their FAQ:

> No, thank you. Even if you can find one (most of them seem to have been registered already, by people who didn't ask whether we actually wanted it before they applied), we're happy with the PuTTY web site being exactly where it is. It's not hard to find (just type ‘putty’ into google.com and we're the first link returned), and we don't believe the administrative hassle of moving the site would be worth the benefit.