It's not surprising though. The very premise of religion insists that one must believe that their religion is the best. After all, if it's not the best, why would practice it? Why would you believe in the rituals, which to an outsider look absurd? The world order is based on becoming moderate - if you stick out too much, you can expect to be eaten (um, or persecuted, jailed, etc). Religion is a method for an outsider to feel included, and to be protected within his or her realm. Don't feel comfortable with something? Join a group of others like you. Then try to convince others to join.
I'm Catholic. I can nail you to any point as to "why my religion is better than yours" - but so can you. My religion, for all honesty, is no better than yours. It's simply different. I can also name a million different ways as to how our religions are parallel, and how they contrast. And that's okay. It's why I practice mine, and why you practice yours (or don't practice any at all). To me, religion is not so much about the belief system - it's about the community that surrounds it. Every religion has different people, and different communities - Catholics act differently than Wiccans, Baptists, and Mormons. We're all raised differently, we find different things acceptable, and we entertain ourselves in different ways. It's a culture.
My family went to a wedding this weekend. The B family is incredibly involved in our church. They sing in the choirs, they head up at least 2 of our annual volunteer committees, they're liaisons with the archdiocese, and all of the kids went to Catholic school. Their oldest daughter, A, went away to college, met, and got engaged to a man. But not a Catholic. A practicing member of the Mormon church. She converted, and they were married in the temple in St. Louis. In my opinion, it's a lovely way to incorporate two cultures. Maybe it's partially the fault of the bride and groom - they made no effort to let Mr. and Mrs. B know that they were welcome to come to the temple for pictures, and that they could wait outside or in a vestibule. Mr. and Mrs. B felt unwelcome, and as so, didn't go to their own daughter's wedding. There are no photos with them and the couple. My parents did nothing but talk terribly about the reception - but considering that the Bs came to my (big Catholic) reception, they felt like they had been shorted. It was mess - and no one was happy in the end. There was absolutely no compromise on either end - even though the guests were split half and half.
Weddings are supposed to be happy. If someone's belief is different from yours, suck it up and at least pretend to be happy. And if you're converting or marrying someone from a different faith, be respectful of ALL of the cultures and religions involved. Don't just stick your nose in the air.
::Steps off soapbox::