Smells like scam
It sounds like a scammer's database, maybe for a robodialer. If you have a big cache of stolen data being used for a crime, you don't want any proof of ownership like holding the password or being the only user in the logs. Tons of bots, curious researchers, and prying eyes is better.
This has happened many times in the past. Maybe El Reg can dig up those articles and find the eventual outcome.
Biting the hand that feeds IT
