I had the same thing, but in Chicago two weeks ago. I was selected for a full "Shakedown" and this guy lokked at every article of clothing and stamp in my passport. I was going for the PremEx level and got 30 minutes of grilling for the trouble. I unfi\ortunately had some generic Tylenol in a plastic bag (because I buy the economy of everything except plane tickets) and he spent ten minutes trying to find the serial number for acetaminophen in the PDF. **Tip of the Week: Take the original packaging!!
I eventually got into town for some Carson's ribs and Goose River Ale.
The funniest thing was though that after the Customs guy was finished rifling through my carry-on, a guy from Booz-Allen wanted me to answer a survey regarding the experience. When I had done the good citizen thing, I was handed a key chain engraved with the U.S.Treasury Service Customs Section logo.
And they did not even kiss me first.