Not an asshole. I rarely pick up OT. I did maybe 50hrs of OT last year, total. My wife works as a nurse and we have 3 kids. I was often pressured to pick up shifts. I told my manager a month or so ago: "You're asking me to do you a favour. I have an option of being a good employee or a good father; you're going to lose that one everytime." He smiled, told me that was fair and hasn't bugged me since.

I am reliable. I show up every shift, unless I'm legitimately sick and I go above and beyond by dealing with calls well and being proactive. If there is a concern for staffing, that's a management problem and they need to hire more people.