MC should adjust its VIP pit on each main stage on a day-to-day basis, considering the headline acts, to avoid those half-empty pits. In 2018 there are plenty of ways to measure expected crowds among concerts (as Primavera has done successfully for the past three years). QOTSA's crowd on the Mad Cool stage obviosuly wasn't as big as Pearl Jam/Arctic Monkeys, and obviously tons of people were waiting for Depeche Mode.
It basically sounds like MC weren't prepared to handle such a massive event in multiple aspects, and it backfired. Such a shame.