They pulled the same trick on me, but I just said no.
Apparently, if you chip in, they mark it as "volunteered", and you get no doe! THAT'S the trick. I don't blame them, but the powers above.
Looking at random day's sick list makes me laugh. More and more guys pull in their sickies. Fair enough if it's our only defense.
I think it starts sinkin' in, allthough it will take time for them to admit and make the connection with their infantile management culture.
So, don't give up, keep it up, it's your health, mental and physical.