I feed my bp in his enclosure. It just seems that he is much more comfortable and less stressed in there.

I feed my Cali king in a separate container just because she is so small and I am worried about the risk of impaction from the Aspen. Once she is bigger I will probably just start feeding her in her enclosure.

I also feed my BCI in a separate enclocure but only because she is a very timid eater and will not eat in front of anyone so I have to put her in a solid color tub with a lid so she can't see out and no one can see in. I have tried watching her and she just won't eat it. As soon as I close the top she downs it in minutes......she's a weirdo

I would say as long as you are in their cages for other reasons besides feeding, ie. cleaning, changing water, handling them, then they will be fine.