Those extensions have now been pulled. http://news.cnet.com/8301-1023_3-57617467-93/google-discards-extensions-that-force-feed-users-ads-in-chrome/
Thanks for the link! That was very informative, and identified at least two of the extensions that were causing problems. Users need to be aware of the dangers still, so the more people are informed about this the better, and also be aware that this could be a potential problem in the future as well.