As you can see in the photos below, it is not allowed to wear shoes inside a Hindu Temple. Moreover, one should not bring shoes inside (*) - they are considered to be dirty (in the spiritual sense). I mentioned it already in my "Does and Don'ts for Indian Travel" post that pointing bottoms of your feet/shoes towards any other person or images and statues of gods is considered to be highly disrespectful and offending. (Also our wedding website informed our guests about this important rule.)
Still, several of our guests brought their shoes inside the temple, and even inside the Vishnu Shrine! When one of the priests noticed it, he went berserk and immediately kicked out those of our guests from the Temple. I'm mentioning this issue to emphasize how important it is to follow rules of other religions if you want to participate in their rituals, or just visit places of importance to them.
Also, it was probably the only major hiccup that happened during our wedding ceremony, so it is fun to look back and laugh at it.
Inside the Temple, in front of the Vishnu Shrine:
Coming back to the Assembly Hall, where our reception was taking place:
(*) Shoes should be left outside the temples, and most of them have a designated place for that purpose, usually just outside the entrance.
(**) One other tip for people visiting Hindu temples: remember to use your right hand for all important things like handing over donations, receiving holy water, handing over money to the shoe storage guy, and pretty much everything else. The left hand is used in the toilet, and is considered dirty.