In my opinion, the church should be classified as a hate group. If the preacher had made similar negative statements toward other groups, such as Jews or blacks, the backlash would be severe and the statements would be rightly considered hate speech. The situation should be no different when such statements are directed at gays.
No, the church should not be classed as a hate group because the claims regarding homosexuality are religious beliefs. The pastor referenced the bible, saying "(The book of) Leviticus says that the earth convulses under the weight of certain human sin. That's natural disasters." He added that he was not specifically targeting gay people, but all types of "sexual sins."
People should be able to speak their mind no matter where they are and no matter what the issue is. Some people do not agree with the homosexual lifestyle. They do not understand it. Every person in the world has a different opinion on every single topic. People should be able to get along and understand that some people to not see things the way other people do.
When I was younger, there was a saying: "Sticks and stones may break my bones but words will never hurt me." I don't know what happened in the last 30 years, but it seems like now everybody wants to outlaw speech that they don't agree with. Having the government with the ability to ban contentious speech is a terrible idea. Soon the definition of "hate groups" will expand to political dissidents, and that's the path to fascism.