DenverBrian, you are correct but I think that the ad's will be the way of the future. I noticed on my ATT wifi account they had an offer for a free one time code if you took a survey and it seemed most of the survey was about what content you would look at for free and if you would be willing to deal with ad's for free limited internet.
Now, I would gladly look at a few ad's at MCI if they could just make their "free" internet worth using.