I feed inside. NEVER had a problem. Last time I was bit was actually when I fed outside.

See, people feed outside because they believe that their python will think they're food if they reach into the tank, like they'll always be expecting food. Large boid owners started using this method, because with a snake that can kill you, you wanna do everything to be safe. Then someone decided if it works for them it'd work for balls.

Feeding outside does nothing for your animal, it is only a measure of protection for yourself. Some balls will refuse to eat if you remove them from their hide, then mve them around, they don't like being disturbed.

I also don't have any harmful substrates. If a person has a substrate like bark they should feed outside.