You missed the rule now on not removing a mask in outdoors to consume alcohol.
Poor behaviour observed, and rules changed now to address the problem.
Not sure why you think there is no enforcement? Many reports of people being fined etc. Unfortunately some do not do what they should.
And yes gatherings have been broken up, and a large one planned prevented from happing.
Selfish people exist, and will seek to end and break. One person in this thread was advocating walking with a different person each day which is hardly minimising mixing. That is 7 households, and if those 7 then walk with others you soon get scores of households.