Here's my take - creating a marketplace where a sole actor has control over a scarce resource (IP addresses) is exactly why anti-trust exists. A true marketplace assumes there is competition. How do you have competition when the underlying resource (1) has a clearly understood finite number (2) is controlled by one entity and (3) can't be differentiated in any way (e.g. 10.0.0.0/8 has no differentiated intrinsic or extrinsic value over 11.0.0.0/8).
If IANA were profit-seeking, they would rent rather than allocate addresses, and force people to pay $10 per IP per year, and roll in the billions of dollars they'd collect.
