She is a Sagittarius, so I think Sagittarius is especially useful. Sagittarius is a free and loose constellation. They don't like being bound by nature. They are more free to do what they want, and they never delay. So is shopping. They can buy whatever they want, so they won't delay all the time.
Moreover, Sagittarius has a strong desire to shop. As long as they feel that they need everything, they may see others buying things. They think, I need it myself, I need to buy it, I will buy it. Then, if others feel that they don't need it and they feel that they need it, they will buy it. They often buy a lot of express delivery, taking more than a dozen at a time. They are really shopaholics.
Actually, I don't think it's a good thing to have such a strong desire to shop. It's true. If your ability cannot support your shopping desire, I think things will get worse. So many times, it is better for us to restrain our desires.