My one exception is at work. I've never really worked out what I'm paid for. If I'm paid to do the same work as everyone else then that's fine but if I'm paid to do everything in my power to achieve company targets then I'm cheating them a bit as I could probably double my productivity by using magic. But I've made the call that work would probably prefer me not to manipulate my customers – they value customer service highly and may see it as a bit immoral – so I choose not to bring my witchcraft to work. I suppose if a weird situation ever arose I'd have to employ it and I did bind a colleague once a few years ago – he's still swinging from my hex tree and I poke him occasionally, lol. But that was personal, not work!
I think its down to using common sense. I can magic off a headache, but why bother when I can just take a paracetamol? Being a bit of a lazy wotsit, I tend to go for the easiest route, sometimes that is magic, sometimes it isn't.
But fundamentally, why would you go to the trouble of studying and practising witchcraft only not to use it when you need it? Magic doesn't run out you know!