Japan is big on fish. You heard it here first. Fish get a respect that transcends their actual role as a foodstuff in a way that chicken and pork will never have, no matter how big of a role they play in the modern Japanese diet. In addition, the more a fish looks like it just leapt out of the ocean and onto your plate the better. A sanitized, cooked fillet is the lowest rung on the fish latter, 活け造り (ikezukuri, a fish filleted alive and presented still gasping), the highest. Fish guts, testes, eggs, and heads are all eaten with gusto. The guest of honor is traditionally presented with the head of the fish being served.
Tai (red snapper) in particular has been a celebration meal staple for a long time. The god of luck/happiness Ebisu (dude on the Ebisu beer cans) is pictured holding a tai. It is a pearly pink color, and red also being a symbol of good luck, it is often the main course at weddings, birthdays, etc. One popular dish that my restaurant just did a run of is 鯛飯 (tai meshi, red snapper rice) in which the rice is cooked in fish stock rather than water and served with the tai on top. The less deconstructed the tai the more high-class the dish; so a really expensive place might serve a whole, non-filleted tai. Other methods (listed in progressively less awe-inspiring order) are splitting the tai in half, using just a fillet, or mixing shredded meat into the rice.
I believe the average American would be pretty horrified at opening the lid to find an open-mouthed fish staring up at them (by the way, the eyes turn white and pop out of the sockets when heated, and if you're not careful, disconnect from the head and roll into the rice; very uncool presentation). The dish itself is nice, but to the disinterested palate a bit underwhelming considering the hype surrounding it. Tai is a good fish. So are a lot of other cheaper and easier-to-cook fish. But this works both ways; a former Japanese teacher confided in me that when she went to America and saw a whole Thanksgiving turkey squatting on the holiday table, she felt physically ill. There's a whole lot of culture and expectation dictating how we feel about a meal. Food isn't just about taste.