You betcha.
The folks that have the chutzpah to criticize others' religious beliefs - other than folks who believe God gave them a right to kill others - make me ill.
They can't prove a damn thing, they have weird beliefs themselves, but never see the "pot calling the kettle black" argument.
It's sad, yet maddening at the same time. The Bible contains some excellent moral principles. It doesn't include crapping on your neighbor's most dearly held beliefs. I think their "backbiting" and snarky attitudes suck.
What exactly can't we prove? Is it particular doctrines like the Trinity, or is your attack more general? If your attack is against Christianity itself that "can't be proved", then all you're saying is that you, who do not value Christianity, cannot understand why Christians value Christ and His church. You don't really offer anything to whether or not Mormonism is really wrong or not. I can certainly disprove its doctrines, and this thread proves Joseph Smith is a false prophet.
For us it is quite serious, souls are at stake, although, naturally, you guys can find no reason why we might want to "criticize others religious beliefs," since your souls are among the totally lost.