You point is easily debunked by the fact that all those late night talk shows (Stephen Colbert, Jon Oliver, Jon Stewart, Seth and so on) haven’t changed a thing in US politics.

Mockery is a great medium for spreading a message. By words don’t make change. Ergo mockery is utterly useless as a weapon for change.

What mockery does do, and petitions too, is placate lazy but opinionated citizens into thinking they’re part of a movement while they can sit in their comfy chair and do a grant total of nothing to actually further their ideologies.