I think you need to be careful where you want to go with this line of thinking. Excessive obesity and Type 2 diabetes due to poor behavior/dietary choices leads to a myriad of increased health costs for everyone, not to mention higher Covid-19 risk, but do we REALLY want to go down that path?
I am obese and have Type 2 diabetes. I used to be underweight, cycled regularly and played sports.
About 20 years ago, I was diagnosed with rheumatoid arthritis. This had a significant impact on my life, because I am an elementary teacher. Elementary schools are freakin' germ factories. You are constantly exposed to bodily fluids with sneezes, hugs, "let's join hands to make a circle," etc . . . I lived far from the school at which I taught, but still cycled to work some days. (1 hour and 15 minute ride.)
I had the option of taking immunosuppressant medication that would alleviate the symptoms so I started doing that. In the first year of my treatment, I was constantly ill, because, while I was not at greater risk of contracting an infection, my immune system didn't let me fight it if I did catch it. I even ended up with pneumonia.
I had a choice to make. I could keep teaching without the meds or find a new job. All of my life I trained to do this one job. It is my passion and my love. I love working with children and felt it was the way I could best contribute in a positive way to society.
I chose to keep teaching. However, without the benefit of medication, my mobility was significantly impacted. I have days when I can't walk or need to use a cane. I tried swimming and cycling, but even the most mild activities are difficult to do some days. Stepping off a curb can be extremely painful and dangerous. I fall more now.
The result is that my activity level dropped, because I was physically incapable of movement on some days. I gained weight. Activity became more difficult. I gained more weight. I got depressed and drank more and ate poorly. I developed Type 2 diabetes.
All this being said, I am completely responsible and accountable for the choices I made. No one made me drink that extra glass of gin or scarf down a Snickers bar. I blame no one else.
My point is, the causes of my health issues aren't entirely rooted in intrinsic laziness. Sometimes things get out of control and you have to work hard to get things back in balance.
I changed jobs last year to just teaching older kids which helps. I went back on medication for arthritis. I've lost a tiny bit of weight, but have a lot more to lose. It will be years. I am now teaching at schools that are within walking/biking distance from my house.
I'm kinda screwed right now, though. I have three risk factors and if I get the virus, I am not statistically in the group that gets to brush this off. I fully anticipate the worse for me if I get it.
Perhaps that is the reason I hope we proceed with caution. We have some data on the virus. We don't know everything. I think we have a responsibility to the most vulnerable members of our society to mitigate the risks as best as possible.
My two cents.