I wouldn't overestimate ICANN's revenue from domain names sales of registries ...

Quote:

ARTICLE 6. FEES 6.1 Registry-Level Fees. Registry Operator shall pay ICANN a Registry-Level Fee equal to (i) the Registry Fixed Fee of US$6,250 per calendar quarter and (ii) the Registry-Level Transaction Fee. The Registry-Level Transaction Fee will be equal to the number of annual increments of an initial or renewal domain name registration (at one or more levels, and including renewals associated with transfers from one ICANN-accredited registrar to another, each a ?Transaction?), during the applicable calendar quarter multiplied by US$0.25; provided, however that the Registry-Level Transaction Fee shall not apply until and unless more than 50,000 Transactions have occurred in the TLD during any calendar quarter or any four calendar quarter period (the ?Transaction Threshold?) and shall apply to each Transaction that occurred during each quarter in which the Transaction Threshold has been met, but shall not apply to each quarter in which the Transaction Threshold has not been met. Registry Operator shall pay the Registry- Level Fees on a quarterly basis by the 20th day following the end of each calendar quarter (i.e., on April 20, July 20, October 20 and January 20 for the calendar quarters ending March 31, June 30, September 30 and December 31) of the year to an account designated by ICANN.