Law enforcement is not a part of the working class. Law enforcement actually represents a very distinct class that does not fall easily into the capitalist/worker paradigm. They are guaranteed economic security, due to state privilege, state employment, police unions and pensions. They are also given special legal status that gives them privilege in respect to acting violently. They don't own the means of production. They do, however, own the means of enforcement on claims of capital. That is a product or service that they have a full monopoly on. And they use it primarily to protect the elite, the state and the individuals at the top of the hierarchy.
It seems to me like giving them wine is some effort at being more humane. I recall reading recently that the "last meal" tradition in the United States had been removed in Texas, because of the idea that they didn't "deserve" any special final meal. Regarding giving the family what they want, I think that would be an improvement. But they should be forced to push the button/pull the switch/pull the trigger. If they want that kind of revenge perhaps emotional burden should be on them to deal with it after the fact. The forms of execution where no one knows who 'technically' killed the person - a firing squad with one empty rifle, a lethal injection with one inert button - those also absolve individuals from responsibility. If people are going to execute others, they need to own that as individuals. Executions become much more difficult when they aren't abstract, as you said.
And even if they only look at the bottom line, they should realize it is a temporary gain for a long-term loss. The whole thing perpetuates a cycle of crime.
It is unlikely that the average individual is going to be harmed by this advice. Your own personal home is not going to become a squat - you will not return home one day and find people living in it. It actually plays out more like this: a bank forecloses on a house and the owners leave (or the owners simply stay and stop paying). The article did end up drawing a line toward the end between stealing from individuals and stealing from large corporations.
I think it would work. It is kind of a broad question - many states that are bad places work. I don't think that a world governments would be desirable. It seems that it would create a power structure with an incredible potential for abuse. If we are to have governments, it is best that they are small and fragmented. At least this way some may be able to provide a safe haven, or a check on unrestrained power. For example, if a state becomes abusive its people may flee elsewhere. If the entire world were one state you're basically stuck with what you have got. This is already a problem due to immigration laws and borders, but it would be absolute in a single worldwide government. I also feel like there are many communities who might want to live in very different ways. A local community may be able to agree and live in harmony with social rules and mores. But if we tried to apply one standard of law to the entire world I think many people would not be content with laws.