Freedom ... ?

The suspense is palpable for those of us who have been wearing face masks as required throughout SE Queensland. We have been told that as soon as Queensland reaches 80% first-dose vaccinations the masks can come off. We had just 0.2% to go at 10:30 on Wednesday (or so I was assured by the wait-person where I picked up a coffee). Of course, you can still wear them if you wish, and I think we may still in some situations. There are heaps of people who seem to have given up wearing masks some time ago ... part of that at least I think is the unclear messages about masks, and mask-wearing, and restrictions.
An example: when we go to Trivia on a Monday night. We don't have to wear a mask until we are at the front door and signing in... and once we have signed in, we take the masks off... and don't wear them again for the two or so hours we are there, until we put them back on to walk the three steps through the foyer and out the front door. I can see why people think there is no reason to wear masks.
What puzzles me is how businesses are supposed to police this. Lots have a sign saying no face mask: no entry, but that doesn't stop people from entering bare-faced. What legal right or responsibility does a business have to prevent non-masked folk from entering - and how would they stop them? Similarly, come the point where 80 per cent of Queensland's (eligible) population is double-dosed and only those who are fully-vaccinated will be able to attend cafes, restaurants, clubs, sporting venues etc, who will be monitoring that? If it's so important, surely there needs to be a system in place to encourage compliance.