I doubt it's due to the Web Host, it's probably due to the Web site's owner (I'm guessing that MAX@ and his colleagues are not Web Hosts but could be wrong, of course).
I guess MAX@ and his colleagues have to find as many ways as possible to find the money to keep ProgArchives going.
However, I do find this avertising technique somewhat odd: a green hyperlink on a few words such as "music", "speakers", "headphones", "flash", "MP3", etc. in these threads and in album reviews. I have to say it does not exactly induce me to go to the advertisers' sites. The "Ads by Goooooogle" in the purple box are more eyecatching, less intrusive, more relevant, and more informative than the green hyperlink ads.
Edited by Fitzcarraldo