Why yes I would call into work for a headache, feeling a little bit sick, or just being sore
I can not preform my job accurately or safely if I am not on the top of my game. If I do not feel well I call into work because if I dont I would be sent home anyway. *It is company policy that you can not work if you are not feeling your best.
Not everyone works in an office (or other job where you can ignore what is going on) where they go all day and having a headache would not be a big deal. If you do that is great but me going to work feeling bad would be dangerous.
ETA: I am an wildlife rehabilitator who works with raptors