It also could have absolutely nothing to do with a fearful mindset and everything to do with employment or other responsibilities.
IIRC Chris' wife is a teacher. Many teachers have already had to quarantine or completely restructure their classrooms because of a Covid outbreak many times. There is only so much sick time given to employees and many have already used all of theirs up.
I know for me personally when I got exposed it caused my contractor to halt work at our house for a week out of caution for protection of him and his employees and other independent contractors (carpet installer, electrician, plumber) who lose money if they cannot work due to Covid.
So I don't assume it is a fear based reaction at all. It could completely be an economic issue, a work flow issue, or "I'm just not wanting to deal with the hassle of being exposed" issue.
But, in the end, they are still concerned or worried about possible outcomes.
https://www.psychologytoday.com/us/blog/science-choice/201812/anxiety-vs-fearAnxiety is seldom pathological, even when intense, until it becomes chronic and consistently interferes with performance and enjoyment of life. When anxiety is excessive and disconnected from reality, it no longer provides an accurate and reliable signal of danger. Thus you might feel anxious thinking about an important exam, going to a dinner party where you don’t know people, or traveling to an unfamiliar place. These anxious thoughts are driven by “what if?” thinking (e.g., “What if I don’t do all my studies?” or “What if I don’t know anyone?”).
Now think of this...If one of her friends she wanted to invite is unvaccinated and she can't attend her friends party. How will that child be affected mentally because she couldn't attend her friends party that they will be discussing and talking all about at school? That child would feel left out of the in-group discussion that was had at the party, in which she becomes the outsider to the discussion of the party.
This pandemic is really affecting people's mindsets. And I am noticing this a lot with people's behaviors, attitudes, and the ways they are actually interacting with others. Some mindsets have changed while others have not, meaning their behaviors and attitudes to those closest to them or, in general, others has not changed. Some people don't even care at all what another person does, but will do whatever to prevent themselves from the others actions.
A great way to witness people's mindsets are while driving. I have a friend who will assume the car in front of her on the slow lane is going to pass the car ahead and will drive slower until they do pass. I tell her, that's what the blinker is for, just pass them and keep going. But people don't use their blinkers, which is why she assumes the other person is suddenly going to jump in front of her and pass, causing her to brake and possibly slide. I actually laughed one time because she got herself frustrated and stressed out because of these assumptions, and I was all to myself, "Well, if you would've went this way instead of going the way you did you wouldn't be frustrated, but you didn't want to drive down this other street because of whatever.

Basically, Cool Chris, my answer is...If people want to go to those lengths to protect themselves, why not. But, there are also outcomes that can have effects mentally and socially that many people are unaware of until the outcome comes to fruition.