Fair enough guess i haven't been to a large event for a while so i'm a bit outdated.
As for an explanation i highly doubt he could hoptis, i've always figured the dogs were there to pander to the media/general public and make up numbers. Plus wrong as it may be they can always twist information in favor of having dogs at events such as there being 26 overdoses at an event with no dogs, Trance Energy, but only 5 at an event with the dogs, Winter Sounds, while ignoring things like people dumping everything before they go in. The general public will buy it every time.