I raised this exact point to a relative on a similar issue (people on the road during a major blizzard).
That said, there are many jobs where you don't need to be there in person. Saying "if you feel sick stay home" (or similar) should be encouraged as it's necessary to enforce this expectation that if you can stay home, you should.
Thanks to the COVID infection I already had and some other illness, I have no sick time left. So if I get it again, I have to take the entire time I'm sick unpaid.
Now I'm lucky in that I can work from home and would do so while able but contagious, and we can afford me to take a few days off unpaid, but plenty of people are in my situation and can't afford a single unpaid day.
I have a coworker who is here with me today ay my job. he's horribly sick and lost his sense of taste but still insists on working and the managers let him. so I'll probably have covid next week.
People are often forced to as many live from salary to salary. My country had a genius idea to reduce longest sick time doctor can prescribe without commission to two weeks from previously two months. Imagine how great that must be for everyone having to work their asses off. Especially considering that a lot of salaries are minimum wages and the rest of the salary is tied through KPI bonuses and stuff. So if you miss a day or two a month there goes majority of your salary.