I personally don't think it's morally wrong to feed a ball python "live" prey. It's called "nature" in my opinion. It is a natural instinct for them to feed on live prey. Regardless of whether or not they are captive they still have the drive to feed on live prey.

As goes for feeding in the tank or out. I feed outside of the tank. All of my snakes are used to it, and it doesn't seem to bother them. I usually wait to remove them from the feeding container until they move around quite a bit after swallowing. But the BIGGEST reason I feed outside of their tank is because if you continue to feed in the tank they will associate food with thier home. I would rather not try to pick one of my snakes up and them mistake me for food.