Regarding TCGs, always buy sealed original boxes with plastic wrap. Do not buy unsealed boxes. Any video evidence or receipts cannot be trusted.

In Japan locally, avoid buying loose packs at convenience stores—they are usually done by kids. Of course, if you're just playing for fun and not serious, there's no problem. After all, it's just leisure, right?
Unless you can buy it offline and see the plastic wrap being cut in front of you, then you can directly sell it at sneaker stores, but that also involves some loss.