system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why is the concept of single-payer or socialized healthcare controversial when we have similar concepts with Fire Departments and Police Departments?

Isn't it basically the same thing? Everyone pays a little bit for these government-run programs in-case one of us needs it, and for the safety and well-being of everyone in their community? How is the Fire/Police Department different from everyone doing the same but for healthcare?
gpt
At one school, there is a tradition of each student donating an small serving of food every day to a communal pool to prevent hunger from affecting the students' studies.

Most students won't need to take anything from the pool since they also bring enough of their own food but sometimes if a parent is too busy to pack lunch or forget to give them lunch money, at least there is something for that student to eat without having a gurgling stomach through the day.

But there are some students that seem always hungry. One student, Johnny, is a bit bigger in both dimensions compared to the other students and gets hungry quite easily. He typically takes more food from the communal pool than the amount he contributes.

Some of the other students are annoyed. They think that because of Johnny's choice to eat more food and become large, he ended up with a big appetite. If he has to eat so much, he should be more self-sufficient and not rely on the communal pool of food because of his own choices. Why do the rest of the students have to pay for Johnny's choices?

But what if Johnny just has a very fast metabolism and being large is genetic? Or what if Johnny's family just does not have enough money to properly feed him? All these issues are beyond what Johnny can control. That is how the communal pool of food can help him remain full and alert during school.