That's the thing though. If someone has an alcohol problem, it will be essential to them. For many, they won't take this as a chance to stay sober.
The magazine is none essential to you, or that particular bread etc. However, if someone, for example, has Autism/Aspergers it could be essential.
Going out to buy a bar of chocolate may be none essential to you, but that's not the case for everyone.
It could be by maintaining some kind of routine it's helping the person deal with the situation mentally.
Everyone has their own coping methods. Doing the daily routine could really be him dealing with it.
Of course, he knows the risk. He has to do this every time he has to go to work. He doesn't need the constant reminders. As a Key Worker, it is all around him. If pushed too soon, its very easy to see how a person would crumble if they admitted to themselves the risk they are constantly making. Chances are he is highly stressed at the moment and even more so depending on the job he does. He may have already been stressed before this.
Remember it's widely recognised that the MH fallout from this afterwards will be huge. It's a fine balance between being stable/unstable mentally already for many. Many already take time off or even quit because of work reduced stress, and that stress doesn't really impact your kidney as much as your mh (I don't think anyway, but you get the idea)
Many people have already had to give up much of their usual pleasures that help to ease stress etc. That thing they are doing more than once a week could be what is left. And even when finding new coping methods, you have to have some in place to help get through. Because when you are looking for new methods normally, things really aren't that good, and normally you would be seeking out the Crisis team if not already there. And that team couldn't cope before this, that's assuming the person has plucked up the courage to contact their GP for help. That's a hard step to take, even harder because of the virus as they will feel incredibly guilty etc.