What you're asking is not Chinese etiquette, it's philosophy. The dominant philosophy in modern Chinese lives is "执输行头 惨过败家". Loosely, it means "never lose out on anything, or else it's worse than wasting away all your family fortune". It is not just mainland Chinese, but even most people in Hong Kong as well.

If you understand this, you'll understand many things you observe in China. For example, on a train, you have to push and get through because it's worse than eating away your family's fortune if you have to stand instead of sitting. Or, why after the nuclear meltdown in Japan, many Chinese went out to buy tonnes of salt literally. They don't care if it's scientific or anything, but if the neighbor is buying salt, it's worse than wasting away your family's fortune to not do the same.

It even applies to government and corporation's practice. That explains why if others have or have done something (like been to the moon, high speed rail, etc), Chinese have to have it too.