You have listed the PR of the directories themselves but people should check the actual PR of the pages that their listing would reside on - which in most cases there is none. Also check that the directory pages are listed in Google - in many cases they are not.
The PR of the directory is meaningless - what counts are the the pages where your site would be listed.
In addition, the cost probably parallels with the PR and since you probably won't be getting your site indexed on the page with all the PR, you will be spending money to put your site on a PR0-1 site when you payed for something like a PR6+.