What is cheapest in the short term is often not the best in the long run. Economics assumes that the long-term consequences are priced into all decisions, but those consequences may not be clear and people with limited means have to make some very hard trade-offs. The costs may also be put on society as a whole and not borne by the individual. It can be helpful to limit those options as a society.

My best guess at the risks is that we may lose something valuable as a society or damage mental health if we push people away from social interaction. Many people will remain healthy, but those who are in difficult circumstances may find themselves on a downward spiral as they are further isolated from their communities. What if your community doesn't have a large supermarket? We talk about food deserts in the US right now, what if we have social deserts?

A simple example of short-term v long-term, look at soda and sugar-sweetened carbonated beverages. They're extremely cheap. Often less expensive than bottles of water in the US. This encourages many people to buy them as they are a cheap source of calories and sweetness. However, it's only many decades later that we've discovered the damage they can do when consumed for long periods of time. Many people consuming them don't have better food options. A few cities are starting to tax them to make the costs more evident.

Gasoline is another good example. The US is addicted to cheap gasoline and doesn't know how to stop even though we are now aware of the potentially catastrophic consequences.