I'm not going to argue that these numbers are grim. But it seems like the study is sampling high consentration areas of the country and implying that these rates are consistent across the US.
Here is a link is to the actual CDC study. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5937a2.htm?s_cid=mm5937a2_w
"MSAs [Metropolitan Statistical Areas]were selected based on high prevalence of acquired immunodeficiency syndrome (AIDS); the 21 MSAs included approximately 60% of all prevalent urban U.S. AIDS cases in 2006."
So basically, they went where the HIV positive men are most consentrated and did a study there, based on concentrations of men in gay bars, gay clubs and gay venues.
But there are a huge number of non-clubbing, non-alcoholic, non-party boy gays out there who actually connect not at these gay scene locations, but through the internet. These guys are not in the survey.