China: luck and joy
Egypt: evil and destruction
Red is a warm color
Red is the most dominant color
Red is sexy and extravagant. It is often used for restaurants, nightclubs, bands and luxury items.
In the middle ages crimson was made from kermes lice which made it very expensive to produce.
Red clothing was only worn by the nobility, the Pope and Cardinals. It was clearly associated with power.
Red is also associated with communism and America's Republican party which seems an odd association.
Sites for bands use red a lot, often as an accent again a black background. Guns and Roses have used these colors to imply excitment and danger but I am not sure if that works totally as the site appears somewhat dated.
It seems apt that Rosso Carmilla would use red considering that its product is fashion accessories for young vampires.
Le 28 Theirs has balanced red well it is not too overwhelming. The colors for this site give a sense of luxury.
I was surprised that the Green Onion had so much red and only one tiny swatch of green considering its name. Their use of the bright red for the page background is a bit overwhelming