1. There are some people who struck it megarich with crypto and now have so much "f-u money" that they are willing to spend it on conspicuous consumption. It is the same sort of thing that comes from "look at how much money I lit on fire" posts being given social credit in places like WSB.
2. There are other people who already had a gazillion dollars and are also interested in conspicuous consumption.
3. NFTs are trendy and trends in the crypto space attract people seeking to make money on a trend. A bunch of people are surely buying these things hoping to leave somebody else holding the bag.
4. It is crypto, so some degree of fraud and crime is involved.