1, the plastic material of yellow bag is usually polystyrene, which is not suitable for making bags, easy to break and expensive, so it is generally not sold as a bag.

2. In some areas, including some rural areas, it is biased to put garbage in yellow bags, so you won't buy them.

3. Yellow bags are used for express delivery, take-away and other occasions because of their striking colors. In these occasions, white and black bags are usually used, so merchants will also purchase goods according to their own needs.