I don't think there is anything wrong with preferring developers who like programming enough to choose to do it in their free time as well. Especially in a startup environment where a bad hire can be devastating.
Is the competency we're proxying for that people "like" programming? Or is the competency that someone is "good at coding"?
I would much prefer someone who's good at the latter than the former. I could care very little whether someone enjoys coding in their free time, I need to know they are competent and work well on a team.
Now that I'm doing the hiring (not something I ever wanted for myself, but we all have to grow up sometime)... I like the people I've hired so far, I would never subject them (or myself) to working with someone who didn't see coding as "more than just a job."