You need to watch the video.
Also, this happened in Mississippi. How many MS judges would let charges like this stand against a group of Christians unless there was some real substance to them?
Why do you think that homosexuals have a right to a festival on the public streets and those who want to protest it don't a right to do so?
WTF? It wasn't in a private building, or grounds. There were no barriers, no admission fees. It was just in the regular, public, open streets.
To finish my thought: people have a right to criticize religion, but they don't have a right to disrupt church services; this would be criminal trespass. So I'm guessing the Christian protestors were in some sense trying to disrupt or impede the parade, a parade which probably had a legal permit and which therefore enjoyed a right to use of the public street without interruption. But I could be wrong, and maybe it was just as it was presented in the story - people being arrested merely for criticizing homosexuality.
The Gays disrupt the St. Patrick's Day parade in South Boston every year. They don't get prosecuted. Gays threw condoms at newly ordained priest at Holy Cross Cathedral, they did not get prosecuted.