As an employer (100+ people), I prefer folks that code outside of work in the same way that I prefer marketing people that study/practice marketing outside of work. For the simple reason that it correlates highly with performance.
What's the sales rep supposed to do in their spare time to study and practice? Or the finance person?
Do I want my surgeon to be studying the latest techniques outside of his work? YES
Do I need a surgeon who dissects animals and removes tumors at home as a hobby on weekends? NO