Scarcity for fun and profit
Cryptocurrency sometimes gets a bad rap for "manufacturing scarcity". Lots of things are scarce for various reasons: gold, endangered species, F1 race cars, etc. Whether for natural or "manufactured" reasons, scarcity isn't inherently a bad thing.
Even with video games, there's typically an abundant supply of the most common items, but the most powerful equipment is rare. This progression is what keeps a lot of games engaging over long periods of time. Players come back because there's better gear to be acquired and they want that sense of satisfaction from collecting it.
There's no denying that game item scarcity is manufactured. The game developers could just as easily give away top tier items to every player for free. But removing the scarcity all together would kill the fun.
Blockchains typically make it difficult and expensive to participate in dApps. This means that historically, dApps have a harder time attracting large audiences. Scarcity is a natural tool to ensure profitability in this environment. It's easier to sell 10,000 NFTs than it would be to sell millions.
As blockchain trends toward mass adoption through cheaper and easier participation, we'll see more dApps that mix abundance and scarcity. Abundance is how you onboard new users. Scarcity is how you keep them engaged.
-Luke
P.S. Two words: supply and demand.