It's once a year. And the idea is to fight back against stigmas that have made such behavior illegal, or grounds for being fired, or having your kids taken away.

I don't know who needs to hear this, but having gay sex in the privacy of your home while you're tied up in a leather harness should not result in those consequences. Display of similar behaviors at Pride are intended to tell the larger world that they aren't going to stop being themselves. People need to grow a thicker skin and get used to the idea, so that Pride isn't necessary any longer.