It’s probably getting on towards bedtime in the Netherlands, so Ingrid may not have seen that Michael Brintnall, executive director of APSA, has “responded in comments”:https://crookedtimber.org/2007/03/07/papers-for-sale/#comment-189268

The annual meeting papers are not meant to be sold, and All Academic is taking them down. It was a mistake that caused them to be up for sale at that site, and we regret it. … The papers are on-line at www.politicalscience.org as part of the PROl initiative. This is an open-access site, operated as a collaboration of APSA and a large number of other political science associations. It’s an extension of APSA’s PROceedings site, where papers are posted for each annual meeting, and it brings together scholarship from a host of other annual meetings too. It’s a good place to search for early scholarship, and I encourage you to use it. All-Academic is the contractor that we use to set up the site. There was some recent confusion about their including our papers in their own for-sale data base. None of the papers from the politicalscience.org project is meant to be at the All Academic site for sale and they are removing them. … I hope this hiccup with All Academic doesn’t fuel any cynicism about making early scholarship like this available on an open access basis – it’s the purpose of the politicalscience.org project, and it’s what academic discourse is about.

This seems to me to be a perfectly gracious response and explanation. As noted in comments, I would like to see APSA consider a different technology – politicalscience.org’s current system has session specific links, which means that e.g. bloggers can’t easily link to interesting political science papers. A system with permalinks like arXiv would allow for much better circulation of political science papers in the general public conversation. But that’s a topic for a different day.