I suspect they would only register names that look somewhat "good". There are plenty of automated ways to valuate domain names -- then just pick the unregistered ones that exceed some value.
You could run a list of available domain names from a domain name suggestion service as lookups using an automated system. You'd want a botnet to avoid getting your IP blocked.
Wasn't the problem that the registrars could retain the domain names without having to pay for a few days? I thought that ICANN had addressed it but am pretty hazy on that point.
