system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 - What’s the difference between “buying low, selling high” and being a scalper?
gpt
There isn't that much difference.  Pretty much all retail sales and resale is based on the idea of buying a product for X, marking it up by Y%, and then selling it for Z.

The issue with scalper is that they insert themselves as _additional_ middle men, marking up the price by _a lot_ because of incredible demand and constrained supply.  People feel they add no value to the process and just extract profits from people because there aren't many units available.

Few people have an issue when Best Buy buys and Xbox for $400 and sells it for $500 because they provide you some value - you can drive to the BB, go into their store and buy the product from their existing stock (which is valuable).  People have an issue with the scalper who buys the Xbox for $500 and sells it for $1,000 because there are no other Xboxes to buy.