The Act is discriminatory. I suggest they might not. Yet when I go to Stonehenge and other events I am a holidaymaker on official leave from work. But this is a kind of racism, and thus threatens public order rather than supporting it. The use of the Act is arbitrary.
Some landlords refuse to use it.
Sometimes police press them, sometimes they remain neutral. Festivals in Wiltshire seem to be seen as a threat to Public Order while in other parts of the country they are not seen as a threat and do not lead to disorders. This suggests that the use of the POA in Wiltshire is just a pretence. In 1988 I heard riot police appeared in a field giving people 10 minutes to leave. This was in the Ogbury area.