What can you buy with Dragon Coins?

Sure, here's a description in English, simulating the tone of a questioner: "Hey there, I've been hearing a lot about Dragon Coins lately, and I'm curious about what exactly I can buy with them. Are they just limited to certain online platforms or can I use them to purchase real-world goods and services? Can I use them to pay for groceries, clothes, or even travel expenses? Or are they more like a digital collectible, only useful within a specific community or game? I'd love to know more about the versatility and practicality of Dragon Coins in the real world. Can you enlighten me?