"Passion" is just a codeword for "is this company your primary focus in your life?"
This actually sounds a lot like what you see when associates leave some big law firms. You aren't given a set amount of PTO ("take whatever you need!" -- not sure if this was the case here), but you'll be judged by how much you take and what you take it for. That, plus your billable hours, and the time you spend at the office on nights and weekends, giving up your personal life to do whatever your partners need, will go into evaluating whether you're a "good fit" for the law firm's culture (i.e., your passion).
The fact is, there are employers who want to be your primary focus in life, and they want to see that from you without having to be prompted, or without having to give you a "passion checklist" to complete. Judging from WC's last discussion, this seems like one of those employers. It can really suck if you're not into playing along, but probably better to figure it out sooner rather than later.