Extension to Hanlon's: never attribute to stupidity what can be attributed to apathy and greed.

This. When it's a person the original quote applies. But big companies have millions of data points on everything and are competent in areas they care about like their own profit. So you can assume it's not ignorance. They don't care if a publisher has to spend loads of time resolving issues rogue ads and malvertising because it doesn't affect them and the end user just blames the publisher.