There are two kinds of "gay" - there is the "gay" as in homosexual, and then the "gay" as in lame/stupid/whatever.
Okay?
Gay Person = that's the human sexuality "gay"
Gay shirt, Gay car, Gay coffee cup = that's the lame/stupid/whatever "gay"
Lets say you're at a bar with your friends, and you see a guy come in to have a beer. You look at his shoes and he's wearing purple clogs - that's gay. But which "gay"?? Well, it is the lame/stupid/whatever gay. If, on the other hand, the guy comes in and starts making out with another guy, then that is "gay" as in sexuality gay.
You've seen the movie Terminator 3, right? Okay, when the Terminator comes out of the bar and puts on the star-shaped sun glasses, those glasses are "gay" - as in lame/stupid/whatever "gay".
However, the male stripper that acts all homo on the stage and tells the Terminator to "tell it to the hand" is gay - as in sexuality gay. (which is weird, because he is a male stripper and there's a room full of women!)