Okay, so if I understand this article correctly, here's what happened:

A anti-gay group was going to give a speech opposing gay rights (they are using their free speech)

A pro-gay group decided to protest the speech (again using their free speech)

The anti-gay group decided to cancel their speech because they thought the protest would generate negative publicitiy (again using their free speech)

Frankly, I don't see what the problem is. Obviously no one's free speech was denied. So are people upset that a speech was being protested? Are you saying, "People shouldn't protest things because those things might be cancelled?" Does that viewpoint make any sense at all?