Why don't you feed?

If you're medically able to, and life's cirstances allow it (i.e.-you work, but are allowed to pump on breaks and produce enough milk), without any medical reason, why wouldn't you feed? I'm just curious. This is a controversial topic and women feel defensive on both sides. Personally, I feed, but have used formula in the past at night for my 4.5 month old, but luckily produce enough to allow exclusive feeding again, even with a full-time job. I know this isn't the case but research says 90% of mothers technically can. I'm just curious. Some say formula is just as good and babies are just as healthy, but yet milk IS more healthy and natural and kids are less likely to get sick. Not a judgement or opinion, that is a proven scientific fact. I just like to hear from other mothers. And believe me, if I couldn't feed, I would give formula with no qualms. I know I'm fortunate, but I also am a proponent for breast feeding since I've been able to do it as a full-time working mom. Let me know. No judgements. Just curious.