That's all their claims. They were not able to show that they were losing or making money in court. There were no records, at all.
However, they would have to been incredibly incompetent not to make millions off the advertisment, based on their amount of traffic. This was key in the procedings.
I mean.. right now thepiratebay.se is at top 90 in the alexa ranking. More traffic than e.g. nytimes.com, ebay.co.uk, redtube.com, dailymail.co.uk, etc etc.
Meanwhile, the hosting cost for this service is comparatively extremely small. Saw some list recently of 20 servers. Perhaps true, but seems inefficient. Still, at that level, peanuts compared to the ad revenue.