First of all, it may be because young people generally tend to spend more rationally now. They have a sense of saving money and are unwilling to spend high prices on some things. However, in the promotion period, there are indeed many discounts on various platforms. They usually buy some very cheap goods during the promotion period, at least much cheaper than usual, which is very attractive. Young people go shopping and like to hoard goods because what they need is cheaper in his place. After all, what they consume is not what they don't need at ordinary times, but some necessities of life or goods they want to buy. When there is a full reduction or discount, naturally young people want to go shopping, but the goods they may buy at that time may not be used immediately, so they will be used later, so they feel like hoarding goods. So the most fundamental factor is that goods are cheaper than usual, attracting young people to go shopping.
Secondly, it is precisely because young people often like to get together to buy express delivery, because it is actually more troublesome to get express delivery every time. So they are more willing to concentrate on getting the courier. When they need to buy goods for a while, they will buy a bunch of things that may not be used for the time being, and then concentrate on getting the express delivery.