I pick up shifts. We all like to do a favor, to make some money.
I picked up four shifts last week, half and half server/hostess. They asked me for one this weekend and I said no.
No one said, 'thank you' for the coverage. But the one I can't do blankets it all, because I said no.
I don't mind doing favors, sometimes I'm even looking for an extra day, and that would be a favor to me due to the extra money. However, I have a life outside of my job. Sometimes I don't want to work an extra shift, sometimes I CAN'T work an extra shift. Why should I be punished for that?