On the flipside, I cannot imagine clickthrough rates and impressions that lead to purchases is high on a site that markets itself as a place to pirate digital content even for those not using adblock. And the nature of the site can deter larger advertisers from using it.
I'm not saying they made no money, but I doubt it would have been as lucrative as if those page views were dedicated to, say, www.wickerbaskets.com or something else.
They don't have any shortage of advertisers so there is obviously demand for the space = companies paying for it. There are also piracy-complementary services that seem to be popular in the ads like VPN and privacy stuff, seed boxes, torrent clients etc that people do pay for.
I really don't think "shortage of advertisers" matters, you can sign up for a Juicy Ads[1] account and place those pop unders and CPM ads on my programming blog if I want, I don't have to communicate with the advertisers I just use an ad platform.
I'm not saying they made no money, but I doubt it would have been as lucrative as if those page views were dedicated to, say, www.wickerbaskets.com or something else.