Fellow feminists, I'm going to say it again for emphasis: It is not your job to explain feminism. As a feminist, it is your job to strive for equality between the genders, and to promote the cause of women wherever you see it flagging. It is your job to keep yourself educated about the issues, and open to new ideas and information.
But it's not your job to explain it.
Look, you can call something anything you want, but that doesn't make it true. I can call my 1986 Saab 9000 a fixie, a Jeep, or a chocolate doughnut. That doesn't make it hipster cool, appropriate for off-road driving, or good with sprinkles.
And yet, some people have the gall to do just that: announce that "X is Y, and devil take the hindmost, it's the gosh-darned truth! Why? Because I said so, that's why!" Sarah Palin is the latest example of this, as she continues to attempt to co-opt the term "feminist" to mean something other than, you know, FEMINIST.
In a nutshell: "Hey Baby!" is a game - maybe more of an art project, really - in which you play a woman who walks down a public street and receives unwelcome attention in the form of catcalls. (Nothing unusual there, I'm afraid.) You then retaliate by opening fire, and killing them.