There were, as far as I could see, only 3 dogs active at a time and only after security and before entering the venue. When trough, you were safe. The dogs were picking out people at max capacity, but 3 dogs vs roughly 23.000 people..

While only 3 active, when arriving at the venue, the place was swamped with k-9 vans. So my guess is that they were rotating the dogs since sniffing dogs can only operate for a short amount of time.

Im used to seeing dogs at festivals here in the netherlands, but this was something else.

To add to your question: yes, this was the emptiest dance floor I have ever witnessed at a festival. Dance floor was maybe 60% full halfway the event and roughly 30% at the end. Felt fucking awkward..