My rats, mice and ASFs are about ten feet from my racks... no problems at all.

I walk past the rodents while handling... when I feed I put the feeder tub in front of the rack, go pour a coffee and by the time I come back everyone is lurking and ready to eat.

I think it is all relative to what they are used to. A rat 10 feet away all the time is normal, then a rat 12 inches away means feeding time.

Bruce