You absolutely can sell ASNs or ASN blocks, just like you can sell IPs.
Want to sell an ASN? Ask the buyer for money. When the money is in your account/escrow, transfer the ASN to them. Get money. Sale complete.
But that’s besides the point, this has got nothing to do with ASNs.
No you can't, because you can't actually acquire an ASN *block* to begin with.
Which is the point of my comment. Only the RIRs handle blocks of ASNs. As a non-RIR entity you can get individual ASNs, or multiple individual ASNs, but not an ASN block.
No, OP used it exactly correctly. It's the textbook definition.
> It normally refers to people extracting money for things far beyond their actual value.
No, it doesn't. The use was popularized in Wealth of Nations (yes, the original) and it refers to, as the name implies, renting out land.
I buy land. Once I've done that, I extract wealth from the economy from the economy while putting nothing new in. There's a finite amount of land.
This contrasts with investing in businesses (which allows them to buy capital, thereby generating further wealth), work, and other forms of income which generate wealth for the economy.
In broad strokes, rent-seeking behavior is unproductive, while work, investment, etc. are productive.
That's not what "rent-seeking" means at all.
Rent-seeking is extracting wealth from a system without creating anything. It's a term meant to differentiate profiting via productivity/adding value (eg. manufacturing a better product and outcompeting others) and profiting via extracting value from others without adding anything (eg. buying out all of the manufacturers of a product and leveraging your monopoly position to jack up prices).
Amazon haven't created any value here - they own enough of a stock of a scarce, in-demand resource that they can charge a great deal for it. It's the definition of rent-seeking.
You can't buy/sell/trade "ASN blocks". The only people handling "ASN blocks" are the 5 RIRs (APNIC, RIPE NCC, ARIN, AfriNIC and LACNIC) and IANA.
It also seems that your use of "rent seeking" doesn't match established use. It normally refers to people extracting money for things far beyond their actual value. The IPv4 market is working pretty well on a supply vs. demand price feedback loop, i.e. the prices are in fact just reflecting the scarcity of IPv4 addresses. The term "rent seeking" does not fit that situation.